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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _send_ffe(self, pid, app_id, app_flags, fr):
 """Send a flood-fill end packet. The cores and regions that the application should be loaded to will have been specified by a stream of flood-fill core select packets (FFCS). """

        arg1 = (NNCommands.flood_fill_end << 24) | pid
        arg2 = (app_id << 24) | (app_flags << 18)
        self._send_scp(255, 255, 0, SCPCommands.nearest_neighbour_packet,
                       arg1, arg2, fr)