This method exposes an API endpoint to
        get the database query string for this slice

def slice_query(self, slice_id):
        """
        This method exposes an API endpoint to
        get the database query string for this slice
        """
        viz_obj = get_viz(slice_id)
        security_manager.assert_datasource_permission(viz_obj.datasource)
        return self.get_query_string_response(viz_obj)