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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 make_index_unique(index: pd.Index, join: str = '-'):
 """Makes the index unique by appending '1', '2', etc. The first occurance of a non-unique value is ignored. Parameters join The connecting string between name and integer. Examples -------- Index(['a', 'b', 'c', 'd', 'b', 'b'], dtype='object') Index(['a', 'b', 'c', 'd', 'b-1', 'b-2'], dtype='object') """

    if index.is_unique:
        return index
    from collections import defaultdict
    values = index.values
    indices_dup = index.duplicated(keep='first')
    values_dup = values[indices_dup]
    counter = defaultdict(lambda: 0)
    for i, v in enumerate(values_dup):
        counter[v] += 1
        values_dup[i] += join + str(counter[v])
    values[indices_dup] = values_dup
    index = pd.Index(values)
    return index