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lib_openzeppelin_contracts/contracts/token/ERC721/extensions/ERC721Votes.sol

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+// SPDX-License-Identifier: MIT
+// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC721/extensions/ERC721Votes.sol)
+
+pragma solidity ^0.8.20;
+
+import {ERC721} from "../ERC721.sol";
+import {Votes} from "../../../governance/utils/Votes.sol";
+
+/**
+ * @dev Extension of ERC-721 to support voting and delegation as implemented by {Votes}, where each individual NFT counts
+ * as 1 vote unit.
+ *
+ * Tokens do not count as votes until they are delegated, because votes must be tracked which incurs an additional cost
+ * on every transfer. Token holders can either delegate to a trusted representative who will decide how to make use of
+ * the votes in governance decisions, or they can delegate to themselves to be their own representative.
+ */
+abstract contract ERC721Votes is ERC721, Votes {
+    /**
+     * @dev See {ERC721-_update}. Adjusts votes when tokens are transferred.
+     *
+     * Emits a {IVotes-DelegateVotesChanged} event.
+     */
+    function _update(address to, uint256 tokenId, address auth) internal virtual override returns (address) {
+        address previousOwner = super._update(to, tokenId, auth);
+
+        _transferVotingUnits(previousOwner, to, 1);
+
+        return previousOwner;
+    }
+
+    /**
+     * @dev Returns the balance of `account`.
+     *
+     * WARNING: Overriding this function will likely result in incorrect vote tracking.
+     */
+    function _getVotingUnits(address account) internal view virtual override returns (uint256) {
+        return balanceOf(account);
+    }
+
+    /**
+     * @dev See {ERC721-_increaseBalance}. We need that to account tokens that were minted in batch.
+     */
+    function _increaseBalance(address account, uint128 amount) internal virtual override {
+        super._increaseBalance(account, amount);
+        _transferVotingUnits(address(0), account, amount);
+    }
+}