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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 get_event_exchange(service_name):
 """ Get an exchange for ``service_name`` events. """

    exchange_name = "{}.events".format(service_name)
    exchange = Exchange(
        exchange_name, type='topic', durable=True, delivery_mode=PERSISTENT
    )

    return exchange