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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 get_duplicates(self):
 """ Extract duplicated index elements. .. deprecated:: 0.23.0 Use idx[idx.duplicated()].unique() instead Returns a sorted list of index elements which appear more than once in the index. Returns ------- array-like List of duplicated indexes. See Also -------- Index.duplicated : Return boolean array denoting duplicates. Index.drop_duplicates : Return Index with duplicates removed. Examples -------- Works on different Index of types. [2, 3] Note that for a DatetimeIndex, it does not return a list but a new DatetimeIndex: DatetimeIndex(['2018-01-03', '2018-01-04'], dtype='datetime64[ns]', freq=None) Sorts duplicated elements even when indexes are unordered. [2, 3] Return empty array-like structure when all elements are unique. [] DatetimeIndex([], dtype='datetime64[ns]', freq=None) """

        warnings.warn("'get_duplicates' is deprecated and will be removed in "
                      "a future release. You can use "
                      "idx[idx.duplicated()].unique() instead",
                      FutureWarning, stacklevel=2)

        return self[self.duplicated()].unique()