def validate(self, args):
        paths_that_should_exist = (
            (args.pkg_1_path, 'PKG_1_PATH'),
            (args.pkg_2_path, 'PKG_2_PATH'),
        )
        try:
            for path, metavar in paths_that_should_exist:
                msg = (metavar, path) % "%s '%s' does not exist"
                assert os.path.exists(path), msg
        except AssertionError as e:
            self._parser.error(str(e))
dataset/ETHPy150Open python-openxml/opc-diag/opcdiag/cli.py/DiffCommand.validate/swapped operands of `%`