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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 sync(self):
 """Retrieve panel information from ElkM1"""

        self._elk.add_handler('VN', self._vn_handler)
        self._elk.add_handler('XK', self._xk_handler)
        self._elk.add_handler('RP', self._rp_handler)
        self._elk.add_handler('IE', self._elk.call_sync_handlers)
        self._elk.add_handler('SS', self._ss_handler)
        self._elk.send(vn_encode())
        self._elk.send(lw_encode())
        self._elk.send(ss_encode())