// File: contracts/OrderOfPermanentInjunction.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.13;

/*
UNITED STATES DISTRICT COURT
SOUTHERN DISTRICT OF NEW YORK
HERMÈS INTERNATIONAL and
HERMÈS OF PARIS, INC.,
Plaintiffs,
-v-
MASON ROTHSCHILD,
Defendant.

22-cv-384 (JSR)
ORDER OF
PERMANENT INJUNCTION

JED S. RAKOFF, U.S.D.J.:

Following a jury trial in which an eight-person jury rendered a unanimous verdict in favor of 
plaintiffs Hermès International and Hermès of Paris, Inc. (collectively, “Hermès”) on its claims for
trademark infringement, trademark dilution, and cybersquatting and determined that the First 
Amendment did not bar defendant Mason Rothschild’s liability on these claims, and for the reasons 
detailed in the Court’s Opinion and Order dated June 23, 2023, it is hereby ORDERED that Rothschild,
and his associates, business partners, influencers, representatives, and all others in active 
concert or participation with him who receive actual notice of this Order, are permanently enjoined 
from:

1. Manufacturing, minting, issuing, producing, distributing, circulating, selling, marketing, 
   offering for sale, advertising, promoting, renting, or otherwise disposing of the “MetaBirkins” 
   non-fungible tokens (“NFTs”) and any merchandise related to the “MetaBirkins” NFTs, including 
   without limitation, listing the “MetaBirkins” NFTs or related merchandise for sale on any 
   marketplace, collecting royalties in connection with the “MetaBirkins” NFTs, and/or otherwise 
   disposing of the “MetaBirkins” NFTs;

2. Making any statement or representation or performing any act that is likely to lead the public to
   believe that any “MetaBirkins” NFTs or related merchandise are in any manner associated or 
   connected with Hermès and/or its “Birkin” trademark and/or trade dress;

3. Using the infringing “MetaBirkins” mark on social media platforms to facilitate the circulation, 
   sale, marketing, advertising, promoting, and renting of the “MetaBirkins” NFTs or related 
   merchandise;

4. Registering, using, or trafficking any domain names or social media or NFT platform usernames or 
   handles that use and/or incorporate the “MetaBirkins” mark; and

5. Providing any benefits to holders of the “MetaBirkins” NFTs, such as airdrops, or otherwise 
   creating incentives for third parties to purchase “MetaBirkins” NFTs.

It is further ORDERED that Rothschild shall, by no later than July 15, 2023, at Rothschild’s 
expense:

1. Transfer any domain names containing the “Birkin” mark to Hermès, including “metabirkins.com”;

2. Contact by e-mail, text, or other written form of communication all persons to whom Rothschild 
   gave, sold, issued, or distributed a “MetaBirkins” NFT or whitelist spot to mint a “MetaBirkins”
   NFT, and provide each of those persons with a copy of this Order; and

3. Airdrop to all “MetaBirkins” NFTs holders a copy of this Order.

It is further ORDERED that Rothschild shall, by no later than June 30, 2023, specify in writing any 
royalties, transfer income, or financial benefits that he has earned from the “MetaBirkins” NFTs 
from January 31, 2023 through June 30, 2023, and shall transfer these earnings to Hermès by no later
than July 15, 2023.

It is further ORDERED that Hermès, Rothschild, and any of Rothschild’s associates, business 
partners, influencers, representatives and other affiliates, and all others in active concert or 
participation with him who receive actual notice of this Order, are enjoined from destroying, 
hiding, dissipating, or altering any documents, including electronic records and social media posts,
that relate in any way to this lawsuit.

It is further ORDERED that, pending the final disposition of any post-trial motion or appeal in this
case, Hermès shall archive the webpage that is currently posted on the “metabirkins.com” website and
on any other domain name that is transferred to it.

It is further ORDERED that Rothschild shall file a declaration under penalty of perjury stating that
he has complied with the foregoing requirements, including a list of all persons to whom he has sent
the required Order, by no later than August 1, 2023.

This Court shall retain jurisdiction over this action for the purpose of implementing and enforcing
this Permanent Injunction
*/

import {ERC721} from "solady/src/tokens/ERC721.sol"; // You got served, Milady
import {Ownable} from "solady/src/auth/Ownable.sol";
import {IERC721OwnerOf} from "../interfaces/IERC721OwnerOf.sol";

contract OrderOfPermanentInjunction is ERC721, Ownable {
    event CompliedWithCourtOrder();

    IERC721OwnerOf public constant OFFENDING_CONTRACT =
        IERC721OwnerOf(0x566b73997F96c1076f7cF9e2C4576Bd08b1A3750);

    constructor() {
        _initializeOwner(msg.sender);
        airdropNotice();
    }

    function airdropNotice() private {
        for (uint256 i; i < 100; ) {
            address tokenOwner = OFFENDING_CONTRACT.ownerOf(i);

            _mint(tokenOwner, i);

            unchecked {
                ++i;
            }
        }

        emit CompliedWithCourtOrder();
    }

    function name() public view virtual override returns (string memory) {
        return "Order of Permanent Injunction";
    }

    function symbol() public view virtual override returns (string memory) {
        return "22-cv-384";
    }

    function tokenURI(
        uint256
    ) public view virtual override returns (string memory) {
        return "ipfs://QmfD33k9cAfd4cTq3jZVVF6NDVFCJK67fjPViCRRe3rr1Z";
    }
}

// File: interfaces/IERC721OwnerOf.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.13;

interface IERC721OwnerOf {
    function ownerOf(uint256 tokenId) external returns (address);
}

// File: solady/src/auth/Ownable.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

/// @notice Simple single owner authorization mixin.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/auth/Ownable.sol)
/// @dev While the ownable portion follows [EIP-173](https://eips.ethereum.org/EIPS/eip-173)
/// for compatibility, the nomenclature for the 2-step ownership handover
/// may be unique to this codebase.
abstract contract Ownable {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       CUSTOM ERRORS                        */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The caller is not authorized to call the function.
    error Unauthorized();

    /// @dev The `newOwner` cannot be the zero address.
    error NewOwnerIsZeroAddress();

    /// @dev The `pendingOwner` does not have a valid handover request.
    error NoHandoverRequest();

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                           EVENTS                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The ownership is transferred from `oldOwner` to `newOwner`.
    /// This event is intentionally kept the same as OpenZeppelin's Ownable to be
    /// compatible with indexers and [EIP-173](https://eips.ethereum.org/EIPS/eip-173),
    /// despite it not being as lightweight as a single argument event.
    event OwnershipTransferred(address indexed oldOwner, address indexed newOwner);

    /// @dev An ownership handover to `pendingOwner` has been requested.
    event OwnershipHandoverRequested(address indexed pendingOwner);

    /// @dev The ownership handover to `pendingOwner` has been canceled.
    event OwnershipHandoverCanceled(address indexed pendingOwner);

    /// @dev `keccak256(bytes("OwnershipTransferred(address,address)"))`.
    uint256 private constant _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE =
        0x8be0079c531659141344cd1fd0a4f28419497f9722a3daafe3b4186f6b6457e0;

    /// @dev `keccak256(bytes("OwnershipHandoverRequested(address)"))`.
    uint256 private constant _OWNERSHIP_HANDOVER_REQUESTED_EVENT_SIGNATURE =
        0xdbf36a107da19e49527a7176a1babf963b4b0ff8cde35ee35d6cd8f1f9ac7e1d;

    /// @dev `keccak256(bytes("OwnershipHandoverCanceled(address)"))`.
    uint256 private constant _OWNERSHIP_HANDOVER_CANCELED_EVENT_SIGNATURE =
        0xfa7b8eab7da67f412cc9575ed43464468f9bfbae89d1675917346ca6d8fe3c92;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                          STORAGE                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The owner slot is given by: `not(_OWNER_SLOT_NOT)`.
    /// It is intentionally chosen to be a high value
    /// to avoid collision with lower slots.
    /// The choice of manual storage layout is to enable compatibility
    /// with both regular and upgradeable contracts.
    uint256 private constant _OWNER_SLOT_NOT = 0x8b78c6d8;

    /// The ownership handover slot of `newOwner` is given by:
    /// ```
    ///     mstore(0x00, or(shl(96, user), _HANDOVER_SLOT_SEED))
    ///     let handoverSlot := keccak256(0x00, 0x20)
    /// ```
    /// It stores the expiry timestamp of the two-step ownership handover.
    uint256 private constant _HANDOVER_SLOT_SEED = 0x389a75e1;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     INTERNAL FUNCTIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Initializes the owner directly without authorization guard.
    /// This function must be called upon initialization,
    /// regardless of whether the contract is upgradeable or not.
    /// This is to enable generalization to both regular and upgradeable contracts,
    /// and to save gas in case the initial owner is not the caller.
    /// For performance reasons, this function will not check if there
    /// is an existing owner.
    function _initializeOwner(address newOwner) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // Clean the upper 96 bits.
            newOwner := shr(96, shl(96, newOwner))
            // Store the new value.
            sstore(not(_OWNER_SLOT_NOT), newOwner)
            // Emit the {OwnershipTransferred} event.
            log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, 0, newOwner)
        }
    }

    /// @dev Sets the owner directly without authorization guard.
    function _setOwner(address newOwner) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            let ownerSlot := not(_OWNER_SLOT_NOT)
            // Clean the upper 96 bits.
            newOwner := shr(96, shl(96, newOwner))
            // Emit the {OwnershipTransferred} event.
            log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, sload(ownerSlot), newOwner)
            // Store the new value.
            sstore(ownerSlot, newOwner)
        }
    }

    /// @dev Throws if the sender is not the owner.
    function _checkOwner() internal view virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // If the caller is not the stored owner, revert.
            if iszero(eq(caller(), sload(not(_OWNER_SLOT_NOT)))) {
                mstore(0x00, 0x82b42900) // `Unauthorized()`.
                revert(0x1c, 0x04)
            }
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  PUBLIC UPDATE FUNCTIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Allows the owner to transfer the ownership to `newOwner`.
    function transferOwnership(address newOwner) public payable virtual onlyOwner {
        /// @solidity memory-safe-assembly
        assembly {
            if iszero(shl(96, newOwner)) {
                mstore(0x00, 0x7448fbae) // `NewOwnerIsZeroAddress()`.
                revert(0x1c, 0x04)
            }
        }
        _setOwner(newOwner);
    }

    /// @dev Allows the owner to renounce their ownership.
    function renounceOwnership() public payable virtual onlyOwner {
        _setOwner(address(0));
    }

    /// @dev Request a two-step ownership handover to the caller.
    /// The request will be automatically expire in 48 hours (172800 seconds) by default.
    function requestOwnershipHandover() public payable virtual {
        unchecked {
            uint256 expires = block.timestamp + ownershipHandoverValidFor();
            /// @solidity memory-safe-assembly
            assembly {
                // Compute and set the handover slot to `expires`.
                mstore(0x0c, _HANDOVER_SLOT_SEED)
                mstore(0x00, caller())
                sstore(keccak256(0x0c, 0x20), expires)
                // Emit the {OwnershipHandoverRequested} event.
                log2(0, 0, _OWNERSHIP_HANDOVER_REQUESTED_EVENT_SIGNATURE, caller())
            }
        }
    }

    /// @dev Cancels the two-step ownership handover to the caller, if any.
    function cancelOwnershipHandover() public payable virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute and set the handover slot to 0.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, caller())
            sstore(keccak256(0x0c, 0x20), 0)
            // Emit the {OwnershipHandoverCanceled} event.
            log2(0, 0, _OWNERSHIP_HANDOVER_CANCELED_EVENT_SIGNATURE, caller())
        }
    }

    /// @dev Allows the owner to complete the two-step ownership handover to `pendingOwner`.
    /// Reverts if there is no existing ownership handover requested by `pendingOwner`.
    function completeOwnershipHandover(address pendingOwner) public payable virtual onlyOwner {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute and set the handover slot to 0.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, pendingOwner)
            let handoverSlot := keccak256(0x0c, 0x20)
            // If the handover does not exist, or has expired.
            if gt(timestamp(), sload(handoverSlot)) {
                mstore(0x00, 0x6f5e8818) // `NoHandoverRequest()`.
                revert(0x1c, 0x04)
            }
            // Set the handover slot to 0.
            sstore(handoverSlot, 0)
        }
        _setOwner(pendingOwner);
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   PUBLIC READ FUNCTIONS                    */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the owner of the contract.
    function owner() public view virtual returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := sload(not(_OWNER_SLOT_NOT))
        }
    }

    /// @dev Returns the expiry timestamp for the two-step ownership handover to `pendingOwner`.
    function ownershipHandoverExpiresAt(address pendingOwner)
        public
        view
        virtual
        returns (uint256 result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the handover slot.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, pendingOwner)
            // Load the handover slot.
            result := sload(keccak256(0x0c, 0x20))
        }
    }

    /// @dev Returns how long a two-step ownership handover is valid for in seconds.
    function ownershipHandoverValidFor() public view virtual returns (uint64) {
        return 48 * 3600;
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                         MODIFIERS                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Marks a function as only callable by the owner.
    modifier onlyOwner() virtual {
        _checkOwner();
        _;
    }
}

// File: solady/src/tokens/ERC721.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

/// @notice Simple ERC721 implementation with storage hitchhiking.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/tokens/ERC721.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)
/// @author Modified from OpenZeppelin (https://github.com/OpenZeppelin/openzeppelin-contracts/tree/master/contracts/token/ERC721/ERC721.sol)
///
/// @dev Note:
/// The ERC721 standard allows for self-approvals.
/// For performance, this implementation WILL NOT revert for such actions.
/// Please add any checks with overrides if desired.
abstract contract ERC721 {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                         CONSTANTS                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev An account can hold up to 4294967295 tokens.
    uint256 internal constant _MAX_ACCOUNT_BALANCE = 0xffffffff;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       CUSTOM ERRORS                        */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Only the token owner or an approved account can manage the token.
    error NotOwnerNorApproved();

    /// @dev The token does not exist.
    error TokenDoesNotExist();

    /// @dev The token already exists.
    error TokenAlreadyExists();

    /// @dev Cannot query the balance for the zero address.
    error BalanceQueryForZeroAddress();

    /// @dev Cannot mint or transfer to the zero address.
    error TransferToZeroAddress();

    /// @dev The token must be owned by `from`.
    error TransferFromIncorrectOwner();

    /// @dev The recipient's balance has overflowed.
    error AccountBalanceOverflow();

    /// @dev Cannot safely transfer to a contract that does not implement
    /// the ERC721Receiver interface.
    error TransferToNonERC721ReceiverImplementer();

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                           EVENTS                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Emitted when token `id` is transferred from `from` to `to`.
    event Transfer(address indexed from, address indexed to, uint256 indexed id);

    /// @dev Emitted when `owner` enables `account` to manage the `id` token.
    event Approval(address indexed owner, address indexed account, uint256 indexed id);

    /// @dev Emitted when `owner` enables or disables `operator` to manage all of their tokens.
    event ApprovalForAll(address indexed owner, address indexed operator, bool isApproved);

    /// @dev `keccak256(bytes("Transfer(address,address,uint256)"))`.
    uint256 private constant _TRANSFER_EVENT_SIGNATURE =
        0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef;

    /// @dev `keccak256(bytes("Approval(address,address,uint256)"))`.
    uint256 private constant _APPROVAL_EVENT_SIGNATURE =
        0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925;

    /// @dev `keccak256(bytes("ApprovalForAll(address,address,bool)"))`.
    uint256 private constant _APPROVAL_FOR_ALL_EVENT_SIGNATURE =
        0x17307eab39ab6107e8899845ad3d59bd9653f200f220920489ca2b5937696c31;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                          STORAGE                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The ownership data slot of `id` is given by:
    /// ```
    ///     mstore(0x00, id)
    ///     mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
    ///     let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
    /// ```
    /// Bits Layout:
    // - [0..159]   `addr`
    // - [160..223] `extraData`
    ///
    /// The approved address slot is given by: `add(1, ownershipSlot)`.
    ///
    /// See: https://notes.ethereum.org/%40vbuterin/verkle_tree_eip
    ///
    /// The balance slot of `owner` is given by:
    /// ```
    ///     mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
    ///     mstore(0x00, owner)
    ///     let balanceSlot := keccak256(0x0c, 0x1c)
    /// ```
    /// Bits Layout:
    /// - [0..31]   `balance`
    /// - [32..225] `aux`
    ///
    /// The `operator` approval slot of `owner` is given by:
    /// ```
    ///     mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, operator))
    ///     mstore(0x00, owner)
    ///     let operatorApprovalSlot := keccak256(0x0c, 0x30)
    /// ```
    uint256 private constant _ERC721_MASTER_SLOT_SEED = 0x7d8825530a5a2e7a << 192;

    /// @dev Pre-shifted and pre-masked constant.
    uint256 private constant _ERC721_MASTER_SLOT_SEED_MASKED = 0x0a5a2e7a00000000;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                      ERC721 METADATA                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the token collection name.
    function name() public view virtual returns (string memory);

    /// @dev Returns the token collection symbol.
    function symbol() public view virtual returns (string memory);

    /// @dev Returns the Uniform Resource Identifier (URI) for token `id`.
    function tokenURI(uint256 id) public view virtual returns (string memory);

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                           ERC721                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the owner of token `id`.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    function ownerOf(uint256 id) public view virtual returns (address result) {
        result = _ownerOf(id);
        /// @solidity memory-safe-assembly
        assembly {
            if iszero(result) {
                mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                revert(0x1c, 0x04)
            }
        }
    }

    /// @dev Returns the number of tokens owned by `owner`.
    ///
    /// Requirements:
    /// - `owner` must not be the zero address.
    function balanceOf(address owner) public view virtual returns (uint256 result) {
        /// @solidity memory-safe-assembly
        assembly {
            // Revert if the `owner` is the zero address.
            if iszero(owner) {
                mstore(0x00, 0x8f4eb604) // `BalanceQueryForZeroAddress()`.
                revert(0x1c, 0x04)
            }
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            mstore(0x00, owner)
            result := and(sload(keccak256(0x0c, 0x1c)), _MAX_ACCOUNT_BALANCE)
        }
    }

    /// @dev Returns the account approved to managed token `id`.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    function getApproved(uint256 id) public view virtual returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            if iszero(shr(96, shl(96, sload(ownershipSlot)))) {
                mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                revert(0x1c, 0x04)
            }
            result := sload(add(1, ownershipSlot))
        }
    }

    /// @dev Sets `account` as the approved account to manage token `id`.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    /// - The caller must be the owner of the token,
    ///   or an approved operator for the token owner.
    ///
    /// Emits a {Approval} event.
    function approve(address account, uint256 id) public payable virtual {
        _approve(msg.sender, account, id);
    }

    /// @dev Returns whether `operator` is approved to manage the tokens of `owner`.
    function isApprovedForAll(address owner, address operator)
        public
        view
        virtual
        returns (bool result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x1c, operator)
            mstore(0x08, _ERC721_MASTER_SLOT_SEED_MASKED)
            mstore(0x00, owner)
            result := sload(keccak256(0x0c, 0x30))
        }
    }

    /// @dev Sets whether `operator` is approved to manage the tokens of the caller.
    ///
    /// Emits a {ApprovalForAll} event.
    function setApprovalForAll(address operator, bool isApproved) public virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // Convert to 0 or 1.
            isApproved := iszero(iszero(isApproved))
            // Update the `isApproved` for (`msg.sender`, `operator`).
            mstore(0x1c, operator)
            mstore(0x08, _ERC721_MASTER_SLOT_SEED_MASKED)
            mstore(0x00, caller())
            sstore(keccak256(0x0c, 0x30), isApproved)
            // Emit the {ApprovalForAll} event.
            mstore(0x00, isApproved)
            log3(
                0x00, 0x20, _APPROVAL_FOR_ALL_EVENT_SIGNATURE, caller(), shr(96, shl(96, operator))
            )
        }
    }

    /// @dev Transfers token `id` from `from` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - `from` must be the owner of the token.
    /// - `to` cannot be the zero address.
    /// - The caller must be the owner of the token, or be approved to manage the token.
    ///
    /// Emits a {Transfer} event.
    function transferFrom(address from, address to, uint256 id) public payable virtual {
        _beforeTokenTransfer(from, to, id);
        /// @solidity memory-safe-assembly
        assembly {
            // Clear the upper 96 bits.
            let bitmaskAddress := shr(96, not(0))
            from := and(bitmaskAddress, from)
            to := and(bitmaskAddress, to)
            // Load the ownership data.
            mstore(0x00, id)
            mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, caller()))
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let ownershipPacked := sload(ownershipSlot)
            let owner := and(bitmaskAddress, ownershipPacked)
            // Revert if `from` is not the owner, or does not exist.
            if iszero(mul(owner, eq(owner, from))) {
                if iszero(owner) {
                    mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                    revert(0x1c, 0x04)
                }
                mstore(0x00, 0xa1148100) // `TransferFromIncorrectOwner()`.
                revert(0x1c, 0x04)
            }
            // Revert if `to` is the zero address.
            if iszero(to) {
                mstore(0x00, 0xea553b34) // `TransferToZeroAddress()`.
                revert(0x1c, 0x04)
            }
            // Load, check, and update the token approval.
            {
                mstore(0x00, from)
                let approvedAddress := sload(add(1, ownershipSlot))
                // Revert if the caller is not the owner, nor approved.
                if iszero(or(eq(caller(), from), eq(caller(), approvedAddress))) {
                    if iszero(sload(keccak256(0x0c, 0x30))) {
                        mstore(0x00, 0x4b6e7f18) // `NotOwnerNorApproved()`.
                        revert(0x1c, 0x04)
                    }
                }
                // Delete the approved address if any.
                if approvedAddress { sstore(add(1, ownershipSlot), 0) }
            }
            // Update with the new owner.
            sstore(ownershipSlot, xor(ownershipPacked, xor(from, to)))
            // Decrement the balance of `from`.
            {
                let fromBalanceSlot := keccak256(0x0c, 0x1c)
                sstore(fromBalanceSlot, sub(sload(fromBalanceSlot), 1))
            }
            // Increment the balance of `to`.
            {
                mstore(0x00, to)
                let toBalanceSlot := keccak256(0x0c, 0x1c)
                let toBalanceSlotPacked := add(sload(toBalanceSlot), 1)
                if iszero(and(toBalanceSlotPacked, _MAX_ACCOUNT_BALANCE)) {
                    mstore(0x00, 0x01336cea) // `AccountBalanceOverflow()`.
                    revert(0x1c, 0x04)
                }
                sstore(toBalanceSlot, toBalanceSlotPacked)
            }
            // Emit the {Transfer} event.
            log4(0x00, 0x00, _TRANSFER_EVENT_SIGNATURE, from, to, id)
        }
        _afterTokenTransfer(from, to, id);
    }

    /// @dev Equivalent to `safeTransferFrom(from, to, id, "")`.
    function safeTransferFrom(address from, address to, uint256 id) public payable virtual {
        transferFrom(from, to, id);
        if (_hasCode(to)) _checkOnERC721Received(from, to, id, "");
    }

    /// @dev Transfers token `id` from `from` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - `from` must be the owner of the token.
    /// - `to` cannot be the zero address.
    /// - The caller must be the owner of the token, or be approved to manage the token.
    /// - 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 id, bytes calldata data)
        public
        payable
        virtual
    {
        transferFrom(from, to, id);
        if (_hasCode(to)) _checkOnERC721Received(from, to, id, data);
    }

    /// @dev Returns true if this contract implements the interface defined by `interfaceId`.
    /// See: https://eips.ethereum.org/EIPS/eip-165
    /// This function call must use less than 30000 gas.
    function supportsInterface(bytes4 interfaceId) public view virtual returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            let s := shr(224, interfaceId)
            // ERC165: 0x01ffc9a7, ERC721: 0x80ac58cd, ERC721Metadata: 0x5b5e139f.
            result := or(or(eq(s, 0x01ffc9a7), eq(s, 0x80ac58cd)), eq(s, 0x5b5e139f))
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  INTERNAL QUERY FUNCTIONS                  */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns if token `id` exists.
    function _exists(uint256 id) internal view virtual returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            result := shl(96, sload(add(id, add(id, keccak256(0x00, 0x20)))))
        }
    }

    /// @dev Returns the owner of token `id`.
    /// Returns the zero address instead of reverting if the token does not exist.
    function _ownerOf(uint256 id) internal view virtual returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            result := shr(96, shl(96, sload(add(id, add(id, keccak256(0x00, 0x20))))))
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*            INTERNAL DATA HITCHHIKING FUNCTIONS             */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the auxiliary data for `owner`.
    /// Minting, transferring, burning the tokens of `owner` will not change the auxiliary data.
    /// Auxiliary data can be set for any address, even if it does not have any tokens.
    function _getAux(address owner) internal view virtual returns (uint224 result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            mstore(0x00, owner)
            result := shr(32, sload(keccak256(0x0c, 0x1c)))
        }
    }

    /// @dev Set the auxiliary data for `owner` to `value`.
    /// Minting, transferring, burning the tokens of `owner` will not change the auxiliary data.
    /// Auxiliary data can be set for any address, even if it does not have any tokens.
    function _setAux(address owner, uint224 value) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            mstore(0x00, owner)
            let balanceSlot := keccak256(0x0c, 0x1c)
            let packed := sload(balanceSlot)
            sstore(balanceSlot, xor(packed, shl(32, xor(value, shr(32, packed)))))
        }
    }

    /// @dev Returns the extra data for token `id`.
    /// Minting, transferring, burning a token will not change the extra data.
    /// The extra data can be set on a non-existent token.
    function _getExtraData(uint256 id) internal view virtual returns (uint96 result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            result := shr(160, sload(add(id, add(id, keccak256(0x00, 0x20)))))
        }
    }

    /// @dev Sets the extra data for token `id` to `value`.
    /// Minting, transferring, burning a token will not change the extra data.
    /// The extra data can be set on a non-existent token.
    function _setExtraData(uint256 id, uint96 value) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let packed := sload(ownershipSlot)
            sstore(ownershipSlot, xor(packed, shl(160, xor(value, shr(160, packed)))))
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  INTERNAL MINT FUNCTIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Mints token `id` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must not exist.
    /// - `to` cannot be the zero address.
    ///
    /// Emits a {Transfer} event.
    function _mint(address to, uint256 id) internal virtual {
        _beforeTokenTransfer(address(0), to, id);
        /// @solidity memory-safe-assembly
        assembly {
            // Clear the upper 96 bits.
            to := shr(96, shl(96, to))
            // Revert if `to` is the zero address.
            if iszero(to) {
                mstore(0x00, 0xea553b34) // `TransferToZeroAddress()`.
                revert(0x1c, 0x04)
            }
            // Load the ownership data.
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let ownershipPacked := sload(ownershipSlot)
            // Revert if the token already exists.
            if shl(96, ownershipPacked) {
                mstore(0x00, 0xc991cbb1) // `TokenAlreadyExists()`.
                revert(0x1c, 0x04)
            }
            // Update with the owner.
            sstore(ownershipSlot, or(ownershipPacked, to))
            // Increment the balance of the owner.
            {
                mstore(0x00, to)
                let balanceSlot := keccak256(0x0c, 0x1c)
                let balanceSlotPacked := add(sload(balanceSlot), 1)
                if iszero(and(balanceSlotPacked, _MAX_ACCOUNT_BALANCE)) {
                    mstore(0x00, 0x01336cea) // `AccountBalanceOverflow()`.
                    revert(0x1c, 0x04)
                }
                sstore(balanceSlot, balanceSlotPacked)
            }
            // Emit the {Transfer} event.
            log4(0x00, 0x00, _TRANSFER_EVENT_SIGNATURE, 0, to, id)
        }
        _afterTokenTransfer(address(0), to, id);
    }

    /// @dev Equivalent to `_safeMint(to, id, "")`.
    function _safeMint(address to, uint256 id) internal virtual {
        _safeMint(to, id, "");
    }

    /// @dev Mints token `id` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must not exist.
    /// - `to` cannot be the zero address.
    /// - 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 id, bytes memory data) internal virtual {
        _mint(to, id);
        if (_hasCode(to)) _checkOnERC721Received(address(0), to, id, data);
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  INTERNAL BURN FUNCTIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Equivalent to `_burn(address(0), id)`.
    function _burn(uint256 id) internal virtual {
        _burn(address(0), id);
    }

    /// @dev Destroys token `id`, using `by`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - If `by` is not the zero address,
    ///   it must be the owner of the token, or be approved to manage the token.
    ///
    /// Emits a {Transfer} event.
    function _burn(address by, uint256 id) internal virtual {
        address owner = ownerOf(id);
        _beforeTokenTransfer(owner, address(0), id);
        /// @solidity memory-safe-assembly
        assembly {
            // Clear the upper 96 bits.
            by := shr(96, shl(96, by))
            // Load the ownership data.
            mstore(0x00, id)
            mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, by))
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let ownershipPacked := sload(ownershipSlot)
            // Reload the owner in case it is changed in `_beforeTokenTransfer`.
            owner := shr(96, shl(96, ownershipPacked))
            // Revert if the token does not exist.
            if iszero(owner) {
                mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                revert(0x1c, 0x04)
            }
            // Load and check the token approval.
            {
                mstore(0x00, owner)
                let approvedAddress := sload(add(1, ownershipSlot))
                // If `by` is not the zero address, do the authorization check.
                // Revert if the `by` is not the owner, nor approved.
                if iszero(or(iszero(by), or(eq(by, owner), eq(by, approvedAddress)))) {
                    if iszero(sload(keccak256(0x0c, 0x30))) {
                        mstore(0x00, 0x4b6e7f18) // `NotOwnerNorApproved()`.
                        revert(0x1c, 0x04)
                    }
                }
                // Delete the approved address if any.
                if approvedAddress { sstore(add(1, ownershipSlot), 0) }
            }
            // Clear the owner.
            sstore(ownershipSlot, xor(ownershipPacked, owner))
            // Decrement the balance of `owner`.
            {
                let balanceSlot := keccak256(0x0c, 0x1c)
                sstore(balanceSlot, sub(sload(balanceSlot), 1))
            }
            // Emit the {Transfer} event.
            log4(0x00, 0x00, _TRANSFER_EVENT_SIGNATURE, owner, 0, id)
        }
        _afterTokenTransfer(owner, address(0), id);
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                INTERNAL APPROVAL FUNCTIONS                 */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns whether `account` is the owner of token `id`, or is approved to managed it.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    function _isApprovedOrOwner(address account, uint256 id)
        internal
        view
        virtual
        returns (bool result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            result := 1
            // Clear the upper 96 bits.
            account := shr(96, shl(96, account))
            // Load the ownership data.
            mstore(0x00, id)
            mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, account))
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let owner := shr(96, shl(96, sload(ownershipSlot)))
            // Revert if the token does not exist.
            if iszero(owner) {
                mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                revert(0x1c, 0x04)
            }
            // Check if `account` is the `owner`.
            if iszero(eq(account, owner)) {
                mstore(0x00, owner)
                // Check if `account` is approved to
                if iszero(sload(keccak256(0x0c, 0x30))) {
                    result := eq(account, sload(add(1, ownershipSlot)))
                }
            }
        }
    }

    /// @dev Returns the account approved to manage token `id`.
    /// Returns the zero address instead of reverting if the token does not exist.
    function _getApproved(uint256 id) internal view virtual returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            result := sload(add(1, add(id, add(id, keccak256(0x00, 0x20)))))
        }
    }

    /// @dev Equivalent to `_approve(address(0), account, id)`.
    function _approve(address account, uint256 id) internal virtual {
        _approve(address(0), account, id);
    }

    /// @dev Sets `account` as the approved account to manage token `id`, using `by`.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    /// - If `by` is not the zero address, `by` must be the owner
    ///   or an approved operator for the token owner.
    ///
    /// Emits a {Transfer} event.
    function _approve(address by, address account, uint256 id) internal virtual {
        assembly {
            // Clear the upper 96 bits.
            let bitmaskAddress := shr(96, not(0))
            account := and(bitmaskAddress, account)
            by := and(bitmaskAddress, by)
            // Load the owner of the token.
            mstore(0x00, id)
            mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, by))
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let owner := and(bitmaskAddress, sload(ownershipSlot))
            // Revert if the token does not exist.
            if iszero(owner) {
                mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                revert(0x1c, 0x04)
            }
            // If `by` is not the zero address, do the authorization check.
            // Revert if `by` is not the owner, nor approved.
            if iszero(or(iszero(by), eq(by, owner))) {
                mstore(0x00, owner)
                if iszero(sload(keccak256(0x0c, 0x30))) {
                    mstore(0x00, 0x4b6e7f18) // `NotOwnerNorApproved()`.
                    revert(0x1c, 0x04)
                }
            }
            // Sets `account` as the approved account to manage `id`.
            sstore(add(1, ownershipSlot), account)
            // Emit the {Approval} event.
            log4(0x00, 0x00, _APPROVAL_EVENT_SIGNATURE, owner, account, id)
        }
    }

    /// @dev Approve or remove the `operator` as an operator for `by`,
    /// without authorization checks.
    ///
    /// Emits a {ApprovalForAll} event.
    function _setApprovalForAll(address by, address operator, bool isApproved) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // Clear the upper 96 bits.
            by := shr(96, shl(96, by))
            operator := shr(96, shl(96, operator))
            // Convert to 0 or 1.
            isApproved := iszero(iszero(isApproved))
            // Update the `isApproved` for (`by`, `operator`).
            mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, operator))
            mstore(0x00, by)
            sstore(keccak256(0x0c, 0x30), isApproved)
            // Emit the {ApprovalForAll} event.
            mstore(0x00, isApproved)
            log3(0x00, 0x20, _APPROVAL_FOR_ALL_EVENT_SIGNATURE, by, operator)
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                INTERNAL TRANSFER FUNCTIONS                 */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Equivalent to `_transfer(address(0), from, to, id)`.
    function _transfer(address from, address to, uint256 id) internal virtual {
        _transfer(address(0), from, to, id);
    }

    /// @dev Transfers token `id` from `from` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - `from` must be the owner of the token.
    /// - `to` cannot be the zero address.
    /// - If `by` is not the zero address,
    ///   it must be the owner of the token, or be approved to manage the token.
    ///
    /// Emits a {Transfer} event.
    function _transfer(address by, address from, address to, uint256 id) internal virtual {
        _beforeTokenTransfer(from, to, id);
        /// @solidity memory-safe-assembly
        assembly {
            // Clear the upper 96 bits.
            let bitmaskAddress := shr(96, not(0))
            from := and(bitmaskAddress, from)
            to := and(bitmaskAddress, to)
            by := and(bitmaskAddress, by)
            // Load the ownership data.
            mstore(0x00, id)
            mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, by))
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let ownershipPacked := sload(ownershipSlot)
            let owner := and(bitmaskAddress, ownershipPacked)
            // Revert if `from` is not the owner, or does not exist.
            if iszero(mul(owner, eq(owner, from))) {
                if iszero(owner) {
                    mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                    revert(0x1c, 0x04)
                }
                mstore(0x00, 0xa1148100) // `TransferFromIncorrectOwner()`.
                revert(0x1c, 0x04)
            }
            // Revert if `to` is the zero address.
            if iszero(to) {
                mstore(0x00, 0xea553b34) // `TransferToZeroAddress()`.
                revert(0x1c, 0x04)
            }
            // Load, check, and update the token approval.
            {
                mstore(0x00, from)
                let approvedAddress := sload(add(1, ownershipSlot))
                // If `by` is not the zero address, do the authorization check.
                // Revert if the `by` is not the owner, nor approved.
                if iszero(or(iszero(by), or(eq(by, from), eq(by, approvedAddress)))) {
                    if iszero(sload(keccak256(0x0c, 0x30))) {
                        mstore(0x00, 0x4b6e7f18) // `NotOwnerNorApproved()`.
                        revert(0x1c, 0x04)
                    }
                }
                // Delete the approved address if any.
                if approvedAddress { sstore(add(1, ownershipSlot), 0) }
            }
            // Update with the new owner.
            sstore(ownershipSlot, xor(ownershipPacked, xor(from, to)))
            // Decrement the balance of `from`.
            {
                let fromBalanceSlot := keccak256(0x0c, 0x1c)
                sstore(fromBalanceSlot, sub(sload(fromBalanceSlot), 1))
            }
            // Increment the balance of `to`.
            {
                mstore(0x00, to)
                let toBalanceSlot := keccak256(0x0c, 0x1c)
                let toBalanceSlotPacked := add(sload(toBalanceSlot), 1)
                if iszero(and(toBalanceSlotPacked, _MAX_ACCOUNT_BALANCE)) {
                    mstore(0x00, 0x01336cea) // `AccountBalanceOverflow()`.
                    revert(0x1c, 0x04)
                }
                sstore(toBalanceSlot, toBalanceSlotPacked)
            }
            // Emit the {Transfer} event.
            log4(0x00, 0x00, _TRANSFER_EVENT_SIGNATURE, from, to, id)
        }
        _afterTokenTransfer(from, to, id);
    }

    /// @dev Equivalent to `_safeTransfer(from, to, id, "")`.
    function _safeTransfer(address from, address to, uint256 id) internal virtual {
        _safeTransfer(from, to, id, "");
    }

    /// @dev Transfers token `id` from `from` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - `from` must be the owner of the token.
    /// - `to` cannot be the zero address.
    /// - The caller must be the owner of the token, or be approved to manage the token.
    /// - 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 id, bytes memory data)
        internal
        virtual
    {
        _transfer(address(0), from, to, id);
        if (_hasCode(to)) _checkOnERC721Received(from, to, id, data);
    }

    /// @dev Equivalent to `_safeTransfer(by, from, to, id, "")`.
    function _safeTransfer(address by, address from, address to, uint256 id) internal virtual {
        _safeTransfer(by, from, to, id, "");
    }

    /// @dev Transfers token `id` from `from` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - `from` must be the owner of the token.
    /// - `to` cannot be the zero address.
    /// - If `by` is not the zero address,
    ///   it must be the owner of the token, or be approved to manage the token.
    /// - 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 by, address from, address to, uint256 id, bytes memory data)
        internal
        virtual
    {
        _transfer(by, from, to, id);
        if (_hasCode(to)) _checkOnERC721Received(from, to, id, data);
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                    HOOKS FOR OVERRIDING                    */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Hook that is called before any token transfers, including minting and burning.
    function _beforeTokenTransfer(address from, address to, uint256 id) internal virtual {}

    /// @dev Hook that is called after any token transfers, including minting and burning.
    function _afterTokenTransfer(address from, address to, uint256 id) internal virtual {}

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                      PRIVATE HELPERS                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns if `a` has bytecode of non-zero length.
    function _hasCode(address a) private view returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := extcodesize(a) // Can handle dirty upper bits.
        }
    }

    /// @dev Perform a call to invoke {IERC721Receiver-onERC721Received} on `to`.
    /// Reverts if the target does not support the function correctly.
    function _checkOnERC721Received(address from, address to, uint256 id, bytes memory data)
        private
    {
        /// @solidity memory-safe-assembly
        assembly {
            // Prepare the calldata.
            let m := mload(0x40)
            let onERC721ReceivedSelector := 0x150b7a02
            mstore(m, onERC721ReceivedSelector)
            mstore(add(m, 0x20), caller()) // The `operator`, which is always `msg.sender`.
            mstore(add(m, 0x40), shr(96, shl(96, from)))
            mstore(add(m, 0x60), id)
            mstore(add(m, 0x80), 0x80)
            let n := mload(data)
            mstore(add(m, 0xa0), n)
            if n { pop(staticcall(gas(), 4, add(data, 0x20), n, add(m, 0xc0), n)) }
            // Revert if the call reverts.
            if iszero(call(gas(), to, 0, add(m, 0x1c), add(n, 0xa4), m, 0x20)) {
                if returndatasize() {
                    // Bubble up the revert if the call reverts.
                    returndatacopy(0x00, 0x00, returndatasize())
                    revert(0x00, returndatasize())
                }
                mstore(m, 0)
            }
            // Load the returndata and compare it.
            if iszero(eq(mload(m), shl(224, onERC721ReceivedSelector))) {
                mstore(0x00, 0xd1a57ed6) // `TransferToNonERC721ReceiverImplementer()`.
                revert(0x1c, 0x04)
            }
        }
    }
}