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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 run(self, *, delay=None):
 """Run this pipeline. Parameters: delay(int):
 The minimum amount of time, in milliseconds, the pipeline should be delayed by. Returns: pipeline: Itself. """

        self.broker.enqueue(self.messages[0], delay=delay)
        return self