def test_non_callable(self):
        with pytest.raises(TypeError) as excinfo:
            event.event(123)
        excinfo.match(r"Expected string, callable or None as first argument")

        with pytest.raises(TypeError) as excinfo:
            event.event("name")([])
        excinfo.match(r"Callable must be a function \(`def`\)"
                      r" or coroutine function \(`async def`\)")
def __getattr__(self, name: str) -> Any:
        """Custom __getattr__ to allow access to metrics schema fields."""

        if name not in self._metric_fields:
            raise AttributeError('No field: {} in metrics.'.format(name))

        return self._values[name]