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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 subscriber(address,topics,callback,message_type):
 """ Creates a subscriber binding to the given address and subscribe the given topics. The callback is invoked for every message received. Args: - address: the address to bind the PUB socket to. - topics: the topics to subscribe - callback: the callback to invoke for every message. Must accept 2 variables - topic and message - message_type: the type of message to receive """

    return Subscriber(address,topics,callback,message_type)