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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_loop(self):
 """ A loop to proceed periodic BFD packet transmission. """

        while self._enable_send:
            hub.sleep(self._xmit_period)

            # Send BFD packet. (RFC5880 Section 6.8.7.)

            if self._remote_discr == 0 and not self._active_role:
                continue

            if self._remote_min_rx_interval == 0:
                continue

            if self._remote_demand_mode and \
                    self._session_state == bfd.BFD_STATE_UP and \
                    self._remote_session_state == bfd.BFD_STATE_UP and \
                    not self._is_polling:
                continue

            self._send()