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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_middleware(exclude=(), append=(), current={'middleware': MIDDLEWARE_CLASSES}):
 """ Returns MIDDLEWARE_CLASSES without the middlewares listed in exclude and with the middlewares listed in append. The use of a mutable dict is intentional, in order to preserve the state of the MIDDLEWARE_CLASSES tuple across multiple settings files. """


    current['middleware'] = tuple(
        [m for m in current['middleware'] if m not in exclude]
    ) + tuple(append)
    return current['middleware']