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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 using(self, timeout=None, key=None, partition=None):
 """Set enqueue specifications such as timeout, key and partition. :param timeout: Job timeout threshold in seconds. If not set, default timeout (specified during queue initialization) is used instead. :type timeout: int | float :param key: Kafka message key. Jobs with the same keys are sent to the same topic partition and executed sequentially. Applies only if the **partition** parameter is not set, and the producer’s partitioner configuration is left as default. For more details on producers, refer to kafka-python's documentation_. :type key: bytes :param partition: Topic partition the message is sent to. If not set, the producer's partitioner selects the partition. For more details on producers, refer to kafka-python's documentation_. :type partition: int :return: Enqueue specification object which has an ``enqueue`` method with the same signature as :func:`kq.queue.Queue.enqueue`. **Example:** .. testcode:: import requests from kafka import KafkaProducer from kq import Job, Queue # Set up a Kafka producer. producer = KafkaProducer(bootstrap_servers='127.0.0.1:9092') # Set up a queue. queue = Queue(topic='topic', producer=producer) url = 'https://www.google.com/' # Enqueue a function call in partition 0 with message key 'foo'. queue.using(partition=0, key=b'foo').enqueue(requests.get, url) # Enqueue a function call with a timeout of 10 seconds. queue.using(timeout=10).enqueue(requests.get, url) # Job values are preferred over values set with "using" method. job = Job(func=requests.get, args=[url], timeout=5) queue.using(timeout=10).enqueue(job) # timeout is still 5 .. _documentation: http://kafka-python.rtfd.io/en/master/#kafkaproducer """

        return EnqueueSpec(
            topic=self._topic,
            producer=self._producer,
            serializer=self._serializer,
            logger=self._logger,
            timeout=timeout or self._timeout,
            key=key,
            partition=partition
        )