Add the constraints for a relationship count query.

        :type query: orator.orm.Builder
        :type parent: orator.orm.Builder

        :rtype: orator.orm.Builder

def get_relation_count_query(self, query, parent):
        """
        Add the constraints for a relationship count query.

        :type query: orator.orm.Builder
        :type parent: orator.orm.Builder

        :rtype: orator.orm.Builder
        """
        if parent.get_query().from__ == query.get_query().from__:
            return self.get_relation_count_query_for_self_join(query, parent)

        self._set_join(query)

        return super(BelongsToMany, self).get_relation_count_query(query, parent)