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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 pop(self):
 """ Pops a task off the front of the queue & runs it. Typically, you'll favor using a ``Worker`` to handle processing the queue (to constantly consume). However, if you need to custom-process the queue in-order, this method is useful. Ex:: # Tasks were previously added, maybe by a different process or finished_topmost_task = gator.pop() :returns: The completed ``Task`` instance """

        data = self.backend.pop(self.queue_name)

        if data:
            task = self.task_class.deserialize(data)
            return self.execute(task)