Solidity importing problem on VSCode (WSL2) and Brownie

Brownie stores library contract data (Chainlink, OpenZeppelin, other dependencies) inside of Users/$yourUsername/.brownie/packages. That's on Mac at least. If you're on Windows, look for a .brownie directory.

To point the Ethereum VS Code extension to these files, you can add a Solidity remapping. This can be done by adding the following:

"solidity.remappings": [
    "@openzeppelin/=/Users/rafi/.brownie/packages/OpenZeppelin/[email protected]"
  ]

to your settings.json file in VS Code. After restarting VS Code, the warning/error should disappear!

Check out the readme for the Ethereum VS Code extension for more info.