def __renumber(dictionary):
    """Renumber the values of the dictionary from 0 to n
    """
    count = 0
    ret = dictionary.copy()
    new_values = dict([])

    for key in dictionary.keys():
        value = dictionary[key]
        new_value = new_values.get(value, -1)
        if new_value == -1:
            new_values[value] = count
            new_value = count
            count += 1
        ret[key] = new_value

    return ret