Decompile the other files

I managed to decompile the main project file, but now how do I decompile the other files that are in the PYZ-00.pyz_extracted folder. I know that some are libraries but I have other files that were created along with the project and that I would like to decompile as well. I tried to use uncompyle6 but I get the error below
ValueError: bad marshal data (unknown type code)