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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 _recursive_cleanup(foo):
 """ Aggressively cleans up things that look empty. """

    if isinstance(foo, dict):
        for (key, val) in list(foo.items()):
            if isinstance(val, dict):
                _recursive_cleanup(val)
            if val == "" or val == [] or val == {}:
                del foo[key]