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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 lock(self):
 """ This method sets a cache variable to mark current job as "already running". """

        if self.cache.get(self.lock_name):
            return False
        else:
            self.cache.set(self.lock_name, timezone.now(), self.timeout)
            return True