ETH Price: $2,043.31 (-1.82%)
Gas: 0.06 Gwei

Transaction Decoder

Block:
16326307 at Jan-03-2023 12:38:11 PM +UTC
Transaction Fee:
0.00058007835 ETH $1.19
Gas Used:
38,289 Gas / 15.15 Gwei

Account State Difference:

  Address   Before After State Difference Code
(Flashbots: Builder)
1.186859190335914559 Eth1.186862947493279213 Eth0.000003757157364654
0xea3e6F05...18f09e3d2
0.12686873389 Eth
Nonce: 453
0.12628865554 Eth
Nonce: 454
0.00058007835

Execution Trace

TransparentUpgradeableProxy.23b872dd( )
  • EarPhone.transferFrom( from=0xea3e6F0517dA612673e3ffCA554B31618f09e3d2, to=0x342daD79376B5A425376A0c75c6C9701B6DE6706, tokenId=4643 )
    File 1 of 2: TransparentUpgradeableProxy
    // File: @openzeppelin/contracts/utils/StorageSlot.sol
    
    
    // OpenZeppelin Contracts (last updated v4.7.0) (utils/StorageSlot.sol)
    
    pragma solidity ^0.8.0;
    
    /**
     * @dev Library for reading and writing primitive types to specific storage slots.
     *
     * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
     * This library helps with reading and writing to such slots without the need for inline assembly.
     *
     * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
     *
     * Example usage to set ERC1967 implementation slot:
     * ```
     * contract ERC1967 {
     *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
     *
     *     function _getImplementation() internal view returns (address) {
     *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
     *     }
     *
     *     function _setImplementation(address newImplementation) internal {
     *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
     *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
     *     }
     * }
     * ```
     *
     * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
     */
    library StorageSlot {
        struct AddressSlot {
            address value;
        }
    
        struct BooleanSlot {
            bool value;
        }
    
        struct Bytes32Slot {
            bytes32 value;
        }
    
        struct Uint256Slot {
            uint256 value;
        }
    
        /**
         * @dev Returns an `AddressSlot` with member `value` located at `slot`.
         */
        function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
    
        /**
         * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
         */
        function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
    
        /**
         * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
         */
        function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
    
        /**
         * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
         */
        function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
    }
    
    // File: @openzeppelin/contracts/utils/Address.sol
    
    
    // OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
    
    pragma solidity ^0.8.1;
    
    /**
     * @dev Collection of functions related to the address type
     */
    library Address {
        /**
         * @dev Returns true if `account` is a contract.
         *
         * [IMPORTANT]
         * ====
         * It is unsafe to assume that an address for which this function returns
         * false is an externally-owned account (EOA) and not a contract.
         *
         * Among others, `isContract` will return false for the following
         * types of addresses:
         *
         *  - an externally-owned account
         *  - a contract in construction
         *  - an address where a contract will be created
         *  - an address where a contract lived, but was destroyed
         * ====
         *
         * [IMPORTANT]
         * ====
         * You shouldn't rely on `isContract` to protect against flash loan attacks!
         *
         * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
         * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
         * constructor.
         * ====
         */
        function isContract(address account) internal view returns (bool) {
            // This method relies on extcodesize/address.code.length, which returns 0
            // for contracts in construction, since the code is only stored at the end
            // of the constructor execution.
    
            return account.code.length > 0;
        }
    
        /**
         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
         * `recipient`, forwarding all available gas and reverting on errors.
         *
         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
         * of certain opcodes, possibly making contracts go over the 2300 gas limit
         * imposed by `transfer`, making them unable to receive funds via
         * `transfer`. {sendValue} removes this limitation.
         *
         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
         *
         * IMPORTANT: because control is transferred to `recipient`, care must be
         * taken to not create reentrancy vulnerabilities. Consider using
         * {ReentrancyGuard} or the
         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
         */
        function sendValue(address payable recipient, uint256 amount) internal {
            require(address(this).balance >= amount, "Address: insufficient balance");
    
            (bool success, ) = recipient.call{value: amount}("");
            require(success, "Address: unable to send value, recipient may have reverted");
        }
    
        /**
         * @dev Performs a Solidity function call using a low level `call`. A
         * plain `call` is an unsafe replacement for a function call: use this
         * function instead.
         *
         * If `target` reverts with a revert reason, it is bubbled up by this
         * function (like regular Solidity function calls).
         *
         * Returns the raw returned data. To convert to the expected return value,
         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
         *
         * Requirements:
         *
         * - `target` must be a contract.
         * - calling `target` with `data` must not revert.
         *
         * _Available since v3.1._
         */
        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionCall(target, data, "Address: low-level call failed");
        }
    
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
         * `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, 0, errorMessage);
        }
    
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but also transferring `value` wei to `target`.
         *
         * Requirements:
         *
         * - the calling contract must have an ETH balance of at least `value`.
         * - the called Solidity function must be `payable`.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
        }
    
        /**
         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
         * with `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(address(this).balance >= value, "Address: insufficient balance for call");
            require(isContract(target), "Address: call to non-contract");
    
            (bool success, bytes memory returndata) = target.call{value: value}(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
    
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
            return functionStaticCall(target, data, "Address: low-level static call failed");
        }
    
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal view returns (bytes memory) {
            require(isContract(target), "Address: static call to non-contract");
    
            (bool success, bytes memory returndata) = target.staticcall(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
    
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionDelegateCall(target, data, "Address: low-level delegate call failed");
        }
    
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(isContract(target), "Address: delegate call to non-contract");
    
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
    
        /**
         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
         * revert reason using the provided one.
         *
         * _Available since v4.3._
         */
        function verifyCallResult(
            bool success,
            bytes memory returndata,
            string memory errorMessage
        ) internal pure returns (bytes memory) {
            if (success) {
                return returndata;
            } else {
                // Look for revert reason and bubble it up if present
                if (returndata.length > 0) {
                    // The easiest way to bubble the revert reason is using memory via assembly
                    /// @solidity memory-safe-assembly
                    assembly {
                        let returndata_size := mload(returndata)
                        revert(add(32, returndata), returndata_size)
                    }
                } else {
                    revert(errorMessage);
                }
            }
        }
    }
    
    // File: @openzeppelin/contracts/interfaces/draft-IERC1822.sol
    
    
    // OpenZeppelin Contracts (last updated v4.5.0) (interfaces/draft-IERC1822.sol)
    
    pragma solidity ^0.8.0;
    
    /**
     * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
     * proxy whose upgrades are fully controlled by the current implementation.
     */
    interface IERC1822Proxiable {
        /**
         * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
         * address.
         *
         * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
         * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
         * function revert if invoked through a proxy.
         */
        function proxiableUUID() external view returns (bytes32);
    }
    
    // File: @openzeppelin/contracts/proxy/beacon/IBeacon.sol
    
    
    // OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
    
    pragma solidity ^0.8.0;
    
    /**
     * @dev This is the interface that {BeaconProxy} expects of its beacon.
     */
    interface IBeacon {
        /**
         * @dev Must return an address that can be used as a delegate call target.
         *
         * {BeaconProxy} will check that this address is a contract.
         */
        function implementation() external view returns (address);
    }
    
    // File: @openzeppelin/contracts/proxy/ERC1967/ERC1967Upgrade.sol
    
    
    // OpenZeppelin Contracts (last updated v4.5.0) (proxy/ERC1967/ERC1967Upgrade.sol)
    
    pragma solidity ^0.8.2;
    
    
    
    
    
    /**
     * @dev This abstract contract provides getters and event emitting update functions for
     * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
     *
     * _Available since v4.1._
     *
     * @custom:oz-upgrades-unsafe-allow delegatecall
     */
    abstract contract ERC1967Upgrade {
        // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
        bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
    
        /**
         * @dev Storage slot with the address of the current implementation.
         * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
         * validated in the constructor.
         */
        bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
    
        /**
         * @dev Emitted when the implementation is upgraded.
         */
        event Upgraded(address indexed implementation);
    
        /**
         * @dev Returns the current implementation address.
         */
        function _getImplementation() internal view returns (address) {
            return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
        }
    
        /**
         * @dev Stores a new address in the EIP1967 implementation slot.
         */
        function _setImplementation(address newImplementation) private {
            require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
            StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
        }
    
        /**
         * @dev Perform implementation upgrade
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeTo(address newImplementation) internal {
            _setImplementation(newImplementation);
            emit Upgraded(newImplementation);
        }
    
        /**
         * @dev Perform implementation upgrade with additional setup call.
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeToAndCall(
            address newImplementation,
            bytes memory data,
            bool forceCall
        ) internal {
            _upgradeTo(newImplementation);
            if (data.length > 0 || forceCall) {
                Address.functionDelegateCall(newImplementation, data);
            }
        }
    
        /**
         * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeToAndCallUUPS(
            address newImplementation,
            bytes memory data,
            bool forceCall
        ) internal {
            // Upgrades from old implementations will perform a rollback test. This test requires the new
            // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
            // this special case will break upgrade paths from old UUPS implementation to new ones.
            if (StorageSlot.getBooleanSlot(_ROLLBACK_SLOT).value) {
                _setImplementation(newImplementation);
            } else {
                try IERC1822Proxiable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                    require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
                } catch {
                    revert("ERC1967Upgrade: new implementation is not UUPS");
                }
                _upgradeToAndCall(newImplementation, data, forceCall);
            }
        }
    
        /**
         * @dev Storage slot with the admin of the contract.
         * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
         * validated in the constructor.
         */
        bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
    
        /**
         * @dev Emitted when the admin account has changed.
         */
        event AdminChanged(address previousAdmin, address newAdmin);
    
        /**
         * @dev Returns the current admin.
         */
        function _getAdmin() internal view returns (address) {
            return StorageSlot.getAddressSlot(_ADMIN_SLOT).value;
        }
    
        /**
         * @dev Stores a new address in the EIP1967 admin slot.
         */
        function _setAdmin(address newAdmin) private {
            require(newAdmin != address(0), "ERC1967: new admin is the zero address");
            StorageSlot.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
        }
    
        /**
         * @dev Changes the admin of the proxy.
         *
         * Emits an {AdminChanged} event.
         */
        function _changeAdmin(address newAdmin) internal {
            emit AdminChanged(_getAdmin(), newAdmin);
            _setAdmin(newAdmin);
        }
    
        /**
         * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
         * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
         */
        bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
    
        /**
         * @dev Emitted when the beacon is upgraded.
         */
        event BeaconUpgraded(address indexed beacon);
    
        /**
         * @dev Returns the current beacon.
         */
        function _getBeacon() internal view returns (address) {
            return StorageSlot.getAddressSlot(_BEACON_SLOT).value;
        }
    
        /**
         * @dev Stores a new beacon in the EIP1967 beacon slot.
         */
        function _setBeacon(address newBeacon) private {
            require(Address.isContract(newBeacon), "ERC1967: new beacon is not a contract");
            require(
                Address.isContract(IBeacon(newBeacon).implementation()),
                "ERC1967: beacon implementation is not a contract"
            );
            StorageSlot.getAddressSlot(_BEACON_SLOT).value = newBeacon;
        }
    
        /**
         * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
         * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
         *
         * Emits a {BeaconUpgraded} event.
         */
        function _upgradeBeaconToAndCall(
            address newBeacon,
            bytes memory data,
            bool forceCall
        ) internal {
            _setBeacon(newBeacon);
            emit BeaconUpgraded(newBeacon);
            if (data.length > 0 || forceCall) {
                Address.functionDelegateCall(IBeacon(newBeacon).implementation(), data);
            }
        }
    }
    
    // File: @openzeppelin/contracts/proxy/Proxy.sol
    
    
    // OpenZeppelin Contracts (last updated v4.6.0) (proxy/Proxy.sol)
    
    pragma solidity ^0.8.0;
    
    /**
     * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
     * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
     * be specified by overriding the virtual {_implementation} function.
     *
     * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
     * different contract through the {_delegate} function.
     *
     * The success and return data of the delegated call will be returned back to the caller of the proxy.
     */
    abstract contract Proxy {
        /**
         * @dev Delegates the current call to `implementation`.
         *
         * This function does not return to its internal call site, it will return directly to the external caller.
         */
        function _delegate(address implementation) internal virtual {
            assembly {
                // Copy msg.data. We take full control of memory in this inline assembly
                // block because it will not return to Solidity code. We overwrite the
                // Solidity scratch pad at memory position 0.
                calldatacopy(0, 0, calldatasize())
    
                // Call the implementation.
                // out and outsize are 0 because we don't know the size yet.
                let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
    
                // Copy the returned data.
                returndatacopy(0, 0, returndatasize())
    
                switch result
                // delegatecall returns 0 on error.
                case 0 {
                    revert(0, returndatasize())
                }
                default {
                    return(0, returndatasize())
                }
            }
        }
    
        /**
         * @dev This is a virtual function that should be overridden so it returns the address to which the fallback function
         * and {_fallback} should delegate.
         */
        function _implementation() internal view virtual returns (address);
    
        /**
         * @dev Delegates the current call to the address returned by `_implementation()`.
         *
         * This function does not return to its internal call site, it will return directly to the external caller.
         */
        function _fallback() internal virtual {
            _beforeFallback();
            _delegate(_implementation());
        }
    
        /**
         * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
         * function in the contract matches the call data.
         */
        fallback() external payable virtual {
            _fallback();
        }
    
        /**
         * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
         * is empty.
         */
        receive() external payable virtual {
            _fallback();
        }
    
        /**
         * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
         * call, or as part of the Solidity `fallback` or `receive` functions.
         *
         * If overridden should call `super._beforeFallback()`.
         */
        function _beforeFallback() internal virtual {}
    }
    
    // File: @openzeppelin/contracts/proxy/ERC1967/ERC1967Proxy.sol
    
    
    // OpenZeppelin Contracts (last updated v4.7.0) (proxy/ERC1967/ERC1967Proxy.sol)
    
    pragma solidity ^0.8.0;
    
    
    
    /**
     * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
     * implementation address that can be changed. This address is stored in storage in the location specified by
     * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
     * implementation behind the proxy.
     */
    contract ERC1967Proxy is Proxy, ERC1967Upgrade {
        /**
         * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
         *
         * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
         * function call, and allows initializing the storage of the proxy like a Solidity constructor.
         */
        constructor(address _logic, bytes memory _data) payable {
            _upgradeToAndCall(_logic, _data, false);
        }
    
        /**
         * @dev Returns the current implementation address.
         */
        function _implementation() internal view virtual override returns (address impl) {
            return ERC1967Upgrade._getImplementation();
        }
    }
    
    // File: default_workspace/TransparentUpgradeableProxy.sol
    
    
    // OpenZeppelin Contracts v4.4.1 (proxy/transparent/TransparentUpgradeableProxy.sol)
    
    pragma solidity ^0.8.0;
    
    
    
    contract TransparentUpgradeableProxy is ERC1967Proxy {
        /**
         * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
         * optionally initialized with `_data` as explained in {ERC1967Proxy-constructor}.
         */
        constructor(
            address _logic,
            address admin_,
            bytes memory _data //0x8129fc1c
        ) payable ERC1967Proxy(_logic, _data) {
            assert(
                _ADMIN_SLOT ==
                    bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1)
            );
            _changeAdmin(admin_);
        }
    
        /**
         * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
         */
        modifier ifAdmin() {
            if (msg.sender == _getAdmin()) {
                _;
            } else {
                _fallback();
            }
        }
    
        /**
         * @dev Returns the current admin.
         *
         * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
         *
         * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
         * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
         * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
         */
        function admin() external ifAdmin returns (address admin_) {
            admin_ = _getAdmin();
        }
    
        /**
         * @dev Returns the current implementation.
         *
         * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
         *
         * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
         * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
         * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
         */
        function implementation()
            external
            ifAdmin
            returns (address implementation_)
        {
            implementation_ = _implementation();
        }
    
        /**
         * @dev Changes the admin of the proxy.
         *
         * Emits an {AdminChanged} event.
         *
         * NOTE: Only the admin can call this function. See {ProxyAdmin-changeProxyAdmin}.
         */
        function changeAdmin(address newAdmin) external virtual ifAdmin {
            _changeAdmin(newAdmin);
        }
    
        /**
         * @dev Upgrade the implementation of the proxy.
         *
         * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
         */
        function upgradeTo(address newImplementation) external ifAdmin {
            _upgradeToAndCall(newImplementation, bytes(""), false);
        }
    
        /**
         * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
         * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
         * proxied contract.
         *
         * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
         */
        function upgradeToAndCall(address newImplementation, bytes calldata data)
            external
            payable
            ifAdmin
        {
            _upgradeToAndCall(newImplementation, data, true);
        }
    
        /**
         * @dev Returns the current admin.
         */
        function _admin() internal view virtual returns (address) {
            return _getAdmin();
        }
    
        /**
         * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
         */
        function _beforeFallback() internal virtual override {
            require(
                msg.sender != _getAdmin(),
                "TransparentUpgradeableProxy: admin cannot fallback to proxy target"
            );
            super._beforeFallback();
        }
    }

    File 2 of 2: EarPhone
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20 {
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
    
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
    
        /**
         * @dev Returns the amount of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
    
        /**
         * @dev Returns the amount of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
    
        /**
         * @dev Moves `amount` tokens from the caller's account to `to`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address to, uint256 amount) external returns (bool);
    
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
    
        /**
         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 amount) external returns (bool);
    
        /**
         * @dev Moves `amount` tokens from `from` to `to` using the
         * allowance mechanism. `amount` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(
            address from,
            address to,
            uint256 amount
        ) external returns (bool);
    }
    
    // File: @openzeppelin/contracts/utils/Strings.sol
    
    
    // OpenZeppelin Contracts v4.4.1 (utils/Strings.sol)
    
    pragma solidity ^0.8.0;
    
    /**
     * @dev String operations.
     */
    library Strings {
        bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
    
        /**
         * @dev Converts a `uint256` to its ASCII `string` decimal representation.
         */
        function toString(uint256 value) internal pure returns (string memory) {
            // Inspired by OraclizeAPI's implementation - MIT licence
            // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
    
            if (value == 0) {
                return "0";
            }
            uint256 temp = value;
            uint256 digits;
            while (temp != 0) {
                digits++;
                temp /= 10;
            }
            bytes memory buffer = new bytes(digits);
            while (value != 0) {
                digits -= 1;
                buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                value /= 10;
            }
            return string(buffer);
        }
    
        /**
         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
         */
        function toHexString(uint256 value) internal pure returns (string memory) {
            if (value == 0) {
                return "0x00";
            }
            uint256 temp = value;
            uint256 length = 0;
            while (temp != 0) {
                length++;
                temp >>= 8;
            }
            return toHexString(value, length);
        }
    
        /**
         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
         */
        function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
            bytes memory buffer = new bytes(2 * length + 2);
            buffer[0] = "0";
            buffer[1] = "x";
            for (uint256 i = 2 * length + 1; i > 1; --i) {
                buffer[i] = _HEX_SYMBOLS[value & 0xf];
                value >>= 4;
            }
            require(value == 0, "Strings: hex length insufficient");
            return string(buffer);
        }
    }
    
    // File: @openzeppelin/contracts/utils/Context.sol
    
    
    // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
    
    pragma solidity ^0.8.0;
    
    /**
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address) {
            return msg.sender;
        }
    
        function _msgData() internal view virtual returns (bytes calldata) {
            return msg.data;
        }
    }
    
    // File: @openzeppelin/contracts/access/Ownable.sol
    
    
    // OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)
    
    pragma solidity ^0.8.0;
    
    
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * By default, the owner account will be the one that deploys the contract. This
     * can later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract Ownable is Context {
        address internal _owner;
    
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    
    
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
    
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            require(owner() == _msgSender(), "Ownable: caller is not the owner");
            _;
        }
    
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions anymore. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby removing any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            _transferOwnership(address(0));
        }
    
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            _transferOwnership(newOwner);
        }
    
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Internal function without access restriction.
         */
        function _transferOwnership(address newOwner) internal virtual {
            address oldOwner = _owner;
            _owner = newOwner;
            emit OwnershipTransferred(oldOwner, newOwner);
        }
    }
    
    // File: @openzeppelin/contracts/utils/Address.sol
    
    
    // OpenZeppelin Contracts (last updated v4.5.0) (utils/Address.sol)
    
    pragma solidity ^0.8.1;
    
    /**
     * @dev Collection of functions related to the address type
     */
    library Address {
        /**
         * @dev Returns true if `account` is a contract.
         *
         * [IMPORTANT]
         * ====
         * It is unsafe to assume that an address for which this function returns
         * false is an externally-owned account (EOA) and not a contract.
         *
         * Among others, `isContract` will return false for the following
         * types of addresses:
         *
         *  - an externally-owned account
         *  - a contract in construction
         *  - an address where a contract will be created
         *  - an address where a contract lived, but was destroyed
         * ====
         *
         * [IMPORTANT]
         * ====
         * You shouldn't rely on `isContract` to protect against flash loan attacks!
         *
         * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
         * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
         * constructor.
         * ====
         */
        function isContract(address account) internal view returns (bool) {
            // This method relies on extcodesize/address.code.length, which returns 0
            // for contracts in construction, since the code is only stored at the end
            // of the constructor execution.
    
            return account.code.length > 0;
        }
    
        /**
         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
         * `recipient`, forwarding all available gas and reverting on errors.
         *
         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
         * of certain opcodes, possibly making contracts go over the 2300 gas limit
         * imposed by `transfer`, making them unable to receive funds via
         * `transfer`. {sendValue} removes this limitation.
         *
         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
         *
         * IMPORTANT: because control is transferred to `recipient`, care must be
         * taken to not create reentrancy vulnerabilities. Consider using
         * {ReentrancyGuard} or the
         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
         */
        function sendValue(address payable recipient, uint256 amount) internal {
            require(address(this).balance >= amount, "Address: insufficient balance");
    
            (bool success, ) = recipient.call{value: amount}("");
            require(success, "Address: unable to send value, recipient may have reverted");
        }
    
        /**
         * @dev Performs a Solidity function call using a low level `call`. A
         * plain `call` is an unsafe replacement for a function call: use this
         * function instead.
         *
         * If `target` reverts with a revert reason, it is bubbled up by this
         * function (like regular Solidity function calls).
         *
         * Returns the raw returned data. To convert to the expected return value,
         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
         *
         * Requirements:
         *
         * - `target` must be a contract.
         * - calling `target` with `data` must not revert.
         *
         * _Available since v3.1._
         */
        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionCall(target, data, "Address: low-level call failed");
        }
    
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
         * `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, 0, errorMessage);
        }
    
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but also transferring `value` wei to `target`.
         *
         * Requirements:
         *
         * - the calling contract must have an ETH balance of at least `value`.
         * - the called Solidity function must be `payable`.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
        }
    
        /**
         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
         * with `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(address(this).balance >= value, "Address: insufficient balance for call");
            require(isContract(target), "Address: call to non-contract");
    
            (bool success, bytes memory returndata) = target.call{value: value}(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
    
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
            return functionStaticCall(target, data, "Address: low-level static call failed");
        }
    
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal view returns (bytes memory) {
            require(isContract(target), "Address: static call to non-contract");
    
            (bool success, bytes memory returndata) = target.staticcall(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
    
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionDelegateCall(target, data, "Address: low-level delegate call failed");
        }
    
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(isContract(target), "Address: delegate call to non-contract");
    
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
    
        /**
         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
         * revert reason using the provided one.
         *
         * _Available since v4.3._
         */
        function verifyCallResult(
            bool success,
            bytes memory returndata,
            string memory errorMessage
        ) internal pure returns (bytes memory) {
            if (success) {
                return returndata;
            } else {
                // Look for revert reason and bubble it up if present
                if (returndata.length > 0) {
                    // The easiest way to bubble the revert reason is using memory via assembly
    
                    assembly {
                        let returndata_size := mload(returndata)
                        revert(add(32, returndata), returndata_size)
                    }
                } else {
                    revert(errorMessage);
                }
            }
        }
    }
    
    // File: @openzeppelin/contracts/token/ERC721/IERC721Receiver.sol
    
    
    // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)
    
    pragma solidity ^0.8.0;
    
    /**
     * @title ERC721 token receiver interface
     * @dev Interface for any contract that wants to support safeTransfers
     * from ERC721 asset contracts.
     */
    interface IERC721Receiver {
        /**
         * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
         * by `operator` from `from`, this function is called.
         *
         * It must return its Solidity selector to confirm the token transfer.
         * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
         *
         * The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.
         */
        function onERC721Received(
            address operator,
            address from,
            uint256 tokenId,
            bytes calldata data
        ) external returns (bytes4);
    }
    
    // File: @openzeppelin/contracts/utils/introspection/IERC165.sol
    
    
    // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
    
    pragma solidity ^0.8.0;
    
    /**
     * @dev Interface of the ERC165 standard, as defined in the
     * https://eips.ethereum.org/EIPS/eip-165[EIP].
     *
     * Implementers can declare support of contract interfaces, which can then be
     * queried by others ({ERC165Checker}).
     *
     * For an implementation, see {ERC165}.
     */
    interface IERC165 {
        /**
         * @dev Returns true if this contract implements the interface defined by
         * `interfaceId`. See the corresponding
         * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
         * to learn more about how these ids are created.
         *
         * This function call must use less than 30 000 gas.
         */
        function supportsInterface(bytes4 interfaceId) external view returns (bool);
    }
    
    // File: @openzeppelin/contracts/utils/introspection/ERC165.sol
    
    
    // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
    
    pragma solidity ^0.8.0;
    
    
    /**
     * @dev Implementation of the {IERC165} interface.
     *
     * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
     * for the additional interface id that will be supported. For example:
     *
     * ```solidity
     * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
     *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
     * }
     * ```
     *
     * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
     */
    abstract contract ERC165 is IERC165 {
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
            return interfaceId == type(IERC165).interfaceId;
        }
    }
    
    // File: @openzeppelin/contracts/token/ERC721/IERC721.sol
    
    
    // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721.sol)
    
    pragma solidity ^0.8.0;
    
    
    /**
     * @dev Required interface of an ERC721 compliant contract.
     */
    interface IERC721 is IERC165 {
        /**
         * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
         */
        event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
    
        /**
         * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
         */
        event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
    
        /**
         * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
         */
        event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
    
        /**
         * @dev Returns the number of tokens in ``owner``'s account.
         */
        function balanceOf(address owner) external view returns (uint256 balance);
    
        /**
         * @dev Returns the owner of the `tokenId` token.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         */
        function ownerOf(uint256 tokenId) external view returns (address owner);
    
        /**
         * @dev Safely transfers `tokenId` token from `from` to `to`.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must exist and be owned by `from`.
         * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId,
            bytes calldata data
        ) external;
    
        /**
         * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
         * are aware of the ERC721 protocol to prevent tokens from being forever locked.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must exist and be owned by `from`.
         * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId
        ) external;
    
        /**
         * @dev Transfers `tokenId` token from `from` to `to`.
         *
         * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must be owned by `from`.
         * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(
            address from,
            address to,
            uint256 tokenId
        ) external;
    
        /**
         * @dev Gives permission to `to` to transfer `tokenId` token to another account.
         * The approval is cleared when the token is transferred.
         *
         * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
         *
         * Requirements:
         *
         * - The caller must own the token or be an approved operator.
         * - `tokenId` must exist.
         *
         * Emits an {Approval} event.
         */
        function approve(address to, uint256 tokenId) external;
    
        /**
         * @dev Approve or remove `operator` as an operator for the caller.
         * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
         *
         * Requirements:
         *
         * - The `operator` cannot be the caller.
         *
         * Emits an {ApprovalForAll} event.
         */
        function setApprovalForAll(address operator, bool _approved) external;
    
        /**
         * @dev Returns the account approved for `tokenId` token.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         */
        function getApproved(uint256 tokenId) external view returns (address operator);
    
        /**
         * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
         *
         * See {setApprovalForAll}
         */
        function isApprovedForAll(address owner, address operator) external view returns (bool);
    }
    
    // File: @openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol
    
    
    // OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)
    
    pragma solidity ^0.8.0;
    
    
    /**
     * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
     * @dev See https://eips.ethereum.org/EIPS/eip-721
     */
    interface IERC721Metadata is IERC721 {
        /**
         * @dev Returns the token collection name.
         */
        function name() external view returns (string memory);
    
        /**
         * @dev Returns the token collection symbol.
         */
        function symbol() external view returns (string memory);
    
        /**
         * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
         */
        function tokenURI(uint256 tokenId) external view returns (string memory);
    }
    
    // File: @openzeppelin/contracts/token/ERC721/ERC721.sol
    
    
    // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/ERC721.sol)
    
    pragma solidity ^0.8.0;
    
    
    
    
    
    
    
    
    /**
     * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
     * the Metadata extension, but not including the Enumerable extension, which is available separately as
     * {ERC721Enumerable}.
     */
    contract ERC721 is Context, ERC165, IERC721, IERC721Metadata {
        using Address for address;
        using Strings for uint256;
    
        // Token name
        string internal _name;
    
        // Token symbol
        string internal _symbol;
    
        // Mapping from token ID to owner address
        mapping(uint256 => address) private _owners;
    
        // Mapping owner address to token count
        mapping(address => uint256) private _balances;
    
        // Mapping from token ID to approved address
        mapping(uint256 => address) private _tokenApprovals;
    
        // Mapping from owner to operator approvals
        mapping(address => mapping(address => bool)) private _operatorApprovals;
    
    
    
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
            return
                interfaceId == type(IERC721).interfaceId ||
                interfaceId == type(IERC721Metadata).interfaceId ||
                super.supportsInterface(interfaceId);
        }
    
        /**
         * @dev See {IERC721-balanceOf}.
         */
        function balanceOf(address owner) public view virtual override returns (uint256) {
            require(owner != address(0), "ERC721: balance query for the zero address");
            return _balances[owner];
        }
    
        /**
         * @dev See {IERC721-ownerOf}.
         */
        function ownerOf(uint256 tokenId) public view virtual override returns (address) {
            address owner = _owners[tokenId];
            require(owner != address(0), "ERC721: owner query for nonexistent token");
            return owner;
        }
    
        /**
         * @dev See {IERC721Metadata-name}.
         */
        function name() public view virtual override returns (string memory) {
            return _name;
        }
    
        /**
         * @dev See {IERC721Metadata-symbol}.
         */
        function symbol() public view virtual override returns (string memory) {
            return _symbol;
        }
    
        /**
         * @dev See {IERC721Metadata-tokenURI}.
         */
        function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
            require(_exists(tokenId), "ERC721Metadata: URI query for nonexistent token");
    
            string memory baseURI = _baseURI();
            return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : "";
        }
    
        /**
         * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
         * token will be the concatenation of the `baseURI` and the `tokenId`. Empty
         * by default, can be overridden in child contracts.
         */
        function _baseURI() internal view virtual returns (string memory) {
            return "";
        }
    
        /**
         * @dev See {IERC721-approve}.
         */
        function approve(address to, uint256 tokenId) public virtual override {
            address owner = ERC721.ownerOf(tokenId);
            require(to != owner, "ERC721: approval to current owner");
    
            require(
                _msgSender() == owner || isApprovedForAll(owner, _msgSender()),
                "ERC721: approve caller is not owner nor approved for all"
            );
    
            _approve(to, tokenId);
        }
    
        /**
         * @dev See {IERC721-getApproved}.
         */
        function getApproved(uint256 tokenId) public view virtual override returns (address) {
            require(_exists(tokenId), "ERC721: approved query for nonexistent token");
    
            return _tokenApprovals[tokenId];
        }
    
        /**
         * @dev See {IERC721-setApprovalForAll}.
         */
        function setApprovalForAll(address operator, bool approved) public virtual override {
            _setApprovalForAll(_msgSender(), operator, approved);
        }
    
        /**
         * @dev See {IERC721-isApprovedForAll}.
         */
        function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
            return _operatorApprovals[owner][operator];
        }
    
        /**
         * @dev See {IERC721-transferFrom}.
         */
        function transferFrom(
            address from,
            address to,
            uint256 tokenId
        ) public virtual override {
            //solhint-disable-next-line max-line-length
            require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
    
            _transfer(from, to, tokenId);
        }
    
        /**
         * @dev See {IERC721-safeTransferFrom}.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId
        ) public virtual override {
            safeTransferFrom(from, to, tokenId, "");
        }
    
        /**
         * @dev See {IERC721-safeTransferFrom}.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId,
            bytes memory _data
        ) public virtual override {
            require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
            _safeTransfer(from, to, tokenId, _data);
        }
    
        /**
         * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
         * are aware of the ERC721 protocol to prevent tokens from being forever locked.
         *
         * `_data` is additional data, it has no specified format and it is sent in call to `to`.
         *
         * This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
         * implement alternative mechanisms to perform token transfer, such as signature-based.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must exist and be owned by `from`.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function _safeTransfer(
            address from,
            address to,
            uint256 tokenId,
            bytes memory _data
        ) internal virtual {
            _transfer(from, to, tokenId);
            require(_checkOnERC721Received(from, to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer");
        }
    
        /**
         * @dev Returns whether `tokenId` exists.
         *
         * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
         *
         * Tokens start existing when they are minted (`_mint`),
         * and stop existing when they are burned (`_burn`).
         */
        function _exists(uint256 tokenId) internal view virtual returns (bool) {
            return _owners[tokenId] != address(0);
        }
    
        /**
         * @dev Returns whether `spender` is allowed to manage `tokenId`.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         */
        function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
            require(_exists(tokenId), "ERC721: operator query for nonexistent token");
            address owner = ERC721.ownerOf(tokenId);
            return (spender == owner || isApprovedForAll(owner, spender) || getApproved(tokenId) == spender);
        }
    
        /**
         * @dev Safely mints `tokenId` and transfers it to `to`.
         *
         * Requirements:
         *
         * - `tokenId` must not exist.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function _safeMint(address to, uint256 tokenId) internal virtual {
            _safeMint(to, tokenId, "");
        }
    
        /**
         * @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
         * forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
         */
        function _safeMint(
            address to,
            uint256 tokenId,
            bytes memory _data
        ) internal virtual {
            _mint(to, tokenId);
            require(
                _checkOnERC721Received(address(0), to, tokenId, _data),
                "ERC721: transfer to non ERC721Receiver implementer"
            );
        }
    
        /**
         * @dev Mints `tokenId` and transfers it to `to`.
         *
         * WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
         *
         * Requirements:
         *
         * - `tokenId` must not exist.
         * - `to` cannot be the zero address.
         *
         * Emits a {Transfer} event.
         */
        function _mint(address to, uint256 tokenId) internal virtual {
            require(to != address(0), "ERC721: mint to the zero address");
            require(!_exists(tokenId), "ERC721: token already minted");
    
            _beforeTokenTransfer(address(0), to, tokenId);
    
            _balances[to] += 1;
            _owners[tokenId] = to;
    
            emit Transfer(address(0), to, tokenId);
    
            _afterTokenTransfer(address(0), to, tokenId);
        }
    
        /**
         * @dev Destroys `tokenId`.
         * The approval is cleared when the token is burned.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         *
         * Emits a {Transfer} event.
         */
        function _burn(uint256 tokenId) internal virtual {
            address owner = ERC721.ownerOf(tokenId);
    
            _beforeTokenTransfer(owner, address(0), tokenId);
    
            // Clear approvals
            _approve(address(0), tokenId);
    
            _balances[owner] -= 1;
            delete _owners[tokenId];
    
            emit Transfer(owner, address(0), tokenId);
    
            _afterTokenTransfer(owner, address(0), tokenId);
        }
    
        /**
         * @dev Transfers `tokenId` from `from` to `to`.
         *  As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
         *
         * Requirements:
         *
         * - `to` cannot be the zero address.
         * - `tokenId` token must be owned by `from`.
         *
         * Emits a {Transfer} event.
         */
        function _transfer(
            address from,
            address to,
            uint256 tokenId
        ) internal virtual {
            require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer from incorrect owner");
            require(to != address(0), "ERC721: transfer to the zero address");
    
            _beforeTokenTransfer(from, to, tokenId);
    
            // Clear approvals from the previous owner
            _approve(address(0), tokenId);
    
            _balances[from] -= 1;
            _balances[to] += 1;
            _owners[tokenId] = to;
    
            emit Transfer(from, to, tokenId);
    
            _afterTokenTransfer(from, to, tokenId);
        }
    
        /**
         * @dev Approve `to` to operate on `tokenId`
         *
         * Emits a {Approval} event.
         */
        function _approve(address to, uint256 tokenId) internal virtual {
            _tokenApprovals[tokenId] = to;
            emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
        }
    
        /**
         * @dev Approve `operator` to operate on all of `owner` tokens
         *
         * Emits a {ApprovalForAll} event.
         */
        function _setApprovalForAll(
            address owner,
            address operator,
            bool approved
        ) internal virtual {
            require(owner != operator, "ERC721: approve to caller");
            _operatorApprovals[owner][operator] = approved;
            emit ApprovalForAll(owner, operator, approved);
        }
    
        /**
         * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
         * The call is not executed if the target address is not a contract.
         *
         * @param from address representing the previous owner of the given token ID
         * @param to target address that will receive the tokens
         * @param tokenId uint256 ID of the token to be transferred
         * @param _data bytes optional data to send along with the call
         * @return bool whether the call correctly returned the expected magic value
         */
        function _checkOnERC721Received(
            address from,
            address to,
            uint256 tokenId,
            bytes memory _data
        ) private returns (bool) {
            if (to.isContract()) {
                try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, _data) returns (bytes4 retval) {
                    return retval == IERC721Receiver.onERC721Received.selector;
                } catch (bytes memory reason) {
                    if (reason.length == 0) {
                        revert("ERC721: transfer to non ERC721Receiver implementer");
                    } else {
                        assembly {
                            revert(add(32, reason), mload(reason))
                        }
                    }
                }
            } else {
                return true;
            }
        }
    
        /**
         * @dev Hook that is called before any token transfer. This includes minting
         * and burning.
         *
         * Calling conditions:
         *
         * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
         * transferred to `to`.
         * - When `from` is zero, `tokenId` will be minted for `to`.
         * - When `to` is zero, ``from``'s `tokenId` will be burned.
         * - `from` and `to` are never both zero.
         *
         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
         */
        function _beforeTokenTransfer(
            address from,
            address to,
            uint256 tokenId
        ) internal virtual {}
    
        /**
         * @dev Hook that is called after any transfer of tokens. This includes
         * minting and burning.
         *
         * Calling conditions:
         *
         * - when `from` and `to` are both non-zero.
         * - `from` and `to` are never both zero.
         *
         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
         */
        function _afterTokenTransfer(
            address from,
            address to,
            uint256 tokenId
        ) internal virtual {}
    }
    
    // File: EarPhone.sol
    
    pragma solidity ^0.8.4;
    
    
    contract EarPhone is ERC721, Ownable {
        bool initialized;
        string public baseURI = "https://www.google.com/";
    
    
        uint256 public COUNTER;
    
        using Strings for uint256;
    	
        function initialize() public 
        {
            require(!initialized, "already initialized");
            COUNTER++;
            _transferOwnership(_msgSender());
            _name = "earPhone";
            _symbol = "EP";
            initialized = true;
           
        }
    	
    	function setBaseURI(string memory _newBaseURI) public onlyOwner {
            baseURI = _newBaseURI;
        }
        function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
            return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : "";
        }
    	
    	
    
    	function batchSafeTransferFrom( uint256[] memory _id,address[] memory _adr) public{
            require(_id.length == _adr.length,"_id len must == _adr len");
            for(uint256 i = 0;i < _adr.length;i++){
                safeTransferFrom(msg.sender,_adr[i], _id[i], '');
            }
    	}
        
       
    	function singleBatchSafeTransferFrom( uint256[] memory _id,address  _adr) public{
    		require(_id.length > 0,"_id len must > 0");
            for(uint256 i = 0;i < _id.length;i++){
                safeTransferFrom(msg.sender,_adr, _id[i], '');
            }
    	}
    	
    	
    
        function mint(
            address[] memory _adr
        ) external onlyOwner {
    		require(_adr.length > 0,"_adr len must > 0");
            for(uint256 i = 0;i < _adr.length;i++){
                _safeMint(_adr[i], COUNTER);
    			COUNTER++;
            }
        }
    	
       
        function singleMint(
            uint256 num,address  _adr
        ) external onlyOwner {
    		require(num > 0,"num must > 0");
            for(uint256 i = 0;i < num;i++){
                _safeMint(_adr, COUNTER);
    			COUNTER++;
            }
        } 
    
        function implodeMint(
            address[] memory _adr,uint256[]  memory _id
        ) external onlyOwner {
    		require(_adr.length > 0,"_adr len must > 0");
            require(_adr.length == _id.length,"_adr len must > 0");
            for(uint256 i = 0;i < _adr.length;i++){
                require( _id[i] >= 100000000,"_adr num is err");
                _safeMint(_adr[i], _id[i]);
            }
        }
    	
    	
    
    
    }