def METHOD_NAME(self) -> None:
    classroom = classroom_config_services.get_classroom_by_url_fragment(
        'math')
    # Ruling out the possibility of None for mypy type checking.
    assert classroom is not None
    self.assertEqual(classroom.to_dict(), self.math_classroom_dict)
    self.assertIsNone(
        classroom_config_services.get_classroom_by_url_fragment(
            'incorrect_url_fragment'))