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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 unique_index(df):
 """ Assert that the index is unique Parameters ========== df : DataFrame Returns ======= df : DataFrame """

    try:
        assert df.index.is_unique
    except AssertionError as e:
        e.args = df.index.get_duplicates()
        raise
    return df