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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 normalize_dict(dictionary, **kwargs):
 """ Given an dict, normalize all of their keys using normalize function. """

    result = {}
    if isinstance(dictionary, dict):
        keys = list(dictionary.keys())
        for key in keys:
            result[normalizer(key, **kwargs)] = normalize_dict(dictionary.get(key), **kwargs)
    else:
        result = dictionary
    return result