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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 unregister(self, thread):
 """ Unregisters an existing thread, so that this thread is no longer available. This function is mainly used during plugin deactivation. :param thread: Name of the thread """

        if thread not in self.threads.keys():
            self.log.warning("Can not unregister thread %s" % thread)
        else:
            del (self.threads[thread])
            self.__log.debug("Thread %s got unregistered" % thread)