def assertCallable(self, obj, msg=None):
        """Same as self.assertTrue(callable(obj)), with a nicer
        default message."""
        if not callable(obj):
            standardMsg = (safe_repr(obj)) % '%s is not callable'
            self.fail(self._formatMessage(msg, standardMsg))
dataset/ETHPy150Open stackdio/stackdio/stackdio/core/tests/utils.py/StackdioTestCase.assertCallable/swapped operands of `%`