def test_type(self):
        rset = event.ResultSet()
        with pytest.raises(NotImplementedError):
            rset.extend([])
        with pytest.raises(NotImplementedError):
            rset.extend(False)
def get_schema(self):
        """Returns the set YAML schema for the metric class.

        Returns:
          YAML schema of the metrics type.
        """
        return self._schema