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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 set_nick(self, nick):
 """Sets or changes your link. This should be called before joining channels, but can be called at any time afterwards. If the requested nickname is not available, the library will keep adding an underscore until a suitable nick is found. """

        self.nick = nick
        self.send_line("NICK {}".format(nick))