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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 ping(self, message=_NOTSET, *, encoding=_NOTSET):
 """Ping the server. Accept optional echo message. """

        if message is not _NOTSET:
            args = (message,)
        else:
            args = ()
        return self.execute('PING', *args, encoding=encoding)