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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_ffcs(self, region, core_mask, fr):
 """Send a flood-fill core select packet. This packet was added in a patched SC&MP 1.34*. Each packet includes a region and a core mask; every core that is in the region ORs the core mask with a mask it stores locally. On receiving a flood-fill end (FFE) packet the application is loaded to the cores specified by this composed core mask. FFCS packets should be sent in ascending order of `(region << 18) | core`. * See https://bitbucket.org/mundya/scamp/branch/new-ff2 """

        arg1 = (NNCommands.flood_fill_core_select << 24) | core_mask
        arg2 = region
        self._send_scp(255, 255, 0, SCPCommands.nearest_neighbour_packet,
                       arg1, arg2, fr)