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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 URLRabbitmqBroker(url, *, middleware=None):
 """Alias for the RabbitMQ broker that takes a connection URL as a positional argument. Parameters: url(str):
 A connection string. middleware(list[Middleware]):
 The middleware to add to this broker. """

    warnings.warn(
        "Use RabbitmqBroker with the 'url' parameter instead of URLRabbitmqBroker.",
        DeprecationWarning, stacklevel=2,
    )
    return RabbitmqBroker(url=url, middleware=middleware)