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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 enable_scp(self, cmd=None):
 """ Enable SCP on remote device. Defaults to Cisco IOS command """

        if cmd is None:
            cmd = ["ip scp server enable"]
        elif not hasattr(cmd, "__iter__"):
            cmd = [cmd]
        self.ssh_ctl_chan.send_config_set(cmd)