'Fetch stored messages with CMGL and add to incoming queue
Return number fetched'

def _fetch_stored_messages(self):

    lines = self.command(('AT+CMGL=%s' % self.smshandler.CMGL_STATUS))
    lines = self._strip_ok(lines)
    messages = self.smshandler.parse_stored_messages(lines)
    for msg in messages:
        self.incoming_queue.append(msg)
