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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 get_alert_destination_count(self, channel=None):
 """Get the number of supported alert destinations :param channel: Channel for alerts to be examined, defaults to current """

        if channel is None:
            channel = self.get_network_channel()
        rqdata = (channel, 0x11, 0, 0)
        rsp = self.xraw_command(netfn=0xc, command=2, data=rqdata)
        return ord(rsp['data'][1])