> For the complete documentation index, see [llms.txt](https://docs.eridian.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.eridian.xyz/ethereum-dev/solidity-notes/openzeppelin.md).

# OpenZeppelin

```solidity
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";

import {ERC20} from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import {ERC721} from "@openzeppelin/contracts/token/ERC721/ERC721.sol";

import {Base64} from "@openzeppelin/contracts/utils/Base64.sol";
```