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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 reserve(cls, queues, res, worker=None, timeout=10):
 """Reserve a job on one of the queues. This marks this job so that other workers will not pick it up. """

        if isinstance(queues, string_types):
            queues = [queues]
        queue, payload = res.pop(queues, timeout=timeout)
        if payload:
            return cls(queue, payload, res, worker)