def constraints_factory():
    """
        Creates a constraints factory for the type of query that is being built.
        This should be overridden by all derived query builders.

        Raises:
            NotImplementedError: This should be overridden by derived query builders.
        Returns:
            An appropriate `pygw.query.query_constraints_factory.QueryConstraintsFactory` for the query type.
        """
    raise NotImplementedError
