Use a solidity version of at least 0.8.13 to get the ability to use using for with a list of free functions
There are 2 instances of this issue:
https://github.com/code-423n4/2022-09-artgobblers/blob/d2087c5a8a6a4f1b9784520e7fe75afa3a9cbdbe/src/Pages.sol#L2
https://github.com/transmissions11/goo-issuance/blob/648e65e66e43ff5c19681427e300ece9c0df1437/src/LibGOO.sol#L2
