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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 enqueue(self, job):
 """Enqueue a job for later processing, returns the new length of the queue """

    if job.queue_name():
      raise EnqueueError("job %s already queued!" % job.job_id)
    new_len = self.redis.lpush(self.queue_name, job.serialize())
    job.notify_queued(self)
    return new_len