def test_complex_schema_item_thirsty_invalid(self):
        serialized = self.schema.serialize()
        with self.assertRaises(jsonschema.exceptions.ValidationError) as excinfo:
            jsonschema.validate({"complex_item": {"thirsty": "Foo"}}, serialized)
        expected = "'Foo' is not of type 'boolean'"
        self.assertIn(expected, excinfo.exception.message)