def assertIsInstance(self, obj, cls, msg=None):
        """Same as self.assertTrue(isinstance(obj, cls)), with a nicer
        default message."""
        if not isinstance(obj, cls):
            standardMsg = '%s is not an instance of %r' % (safe_repr(obj), cls)
            self.fail(self._formatMessage(msg, standardMsg))
dataset/ETHPy150Open kleientertainment/ds_mod_tools/pkg/win32/Python27/Lib/unittest/case.py/TestCase.assertIsInstance/original