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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 removeSubscriber(self, email):
 """Remove a subscriber from this workitem If the subscriber has not been added, no more actions will be performed. :param email: the subscriber's email """


        headers, raw_data = self._perform_subscribe()
        missing_flag, raw_data = self._remove_subscriber(email, raw_data)
        if missing_flag:
            return

        self._update_subscribe(headers, raw_data)
        self.log.info("Successfully remove a subscriber: %s for <Workitem %s>",
                      email, self)