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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 shutdown(self):
 """Stops all active periodic tasks and closes the socket."""

        self.stop_all_periodic_tasks()
        for channel in self._bcm_sockets:
            log.debug("Closing bcm socket for channel {}".format(channel))
            bcm_socket = self._bcm_sockets[channel]
            bcm_socket.close()
        log.debug("Closing raw can socket")
        self.socket.close()