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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 dict_max(dic):
 """ Returns maximum value of a dictionary. """

    aux = dict(map(lambda item: (item[1],item[0]),dic.items()))
    if aux.keys() == []:
        return 0
    max_value = max(aux.keys())
    return max_value,aux[max_value]