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


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