def _get_subresource(self, qs):
        r = []

        # Split the querystring
        keys = qs.split('&')
        # for each item
        for i in keys:
            # get the key
            item = i.split('=')
            k = item[0].lower()

            # If it's one the special params
            if k in AWS_QUERY_PARAMS:
                # add it to our result list
                r.append(i)

        # If we have result, convert them to query string
        if r:
            return '?' + '&'.join(r)

        return ''
Override this method so that it flushes the vtk pipeline if
dataset/ETHPy150Open smore-inc/tinys3/tinys3/auth.py/S3Auth._get_subresource--crossover with--dataset/ETHPy150Open enthought/mayavi/mayavi/modules/contour_grid_plane.py/ContourGridPlane.update_data