def duplicated(self, keep='<STR_LIT>'):
return super().duplicated(keep=keep)<EOL>
Indicate duplicate Series values.

Duplicated values are indicated as ``True`` values in the resulting
Series. Either all duplicates, all except the first or all except the
last occurrence of duplicates can be indicated.

Parameters
----------
keep : {'first', 'last', False}, default 'first'
    - 'first' : Mark duplicates as ``True`` except for the first
      occurrence.
    - 'last' : Mark duplicates as ``True`` except for the last
      occurrence.
    - ``False`` : Mark all duplicates as ``True``.

Returns
-------
Series
    Series indicating whether each value has occurred in the
    preceding values.

See Also
--------
Index.duplicated : Equivalent method on pandas.Index.
DataFrame.duplicated : Equivalent method on pandas.DataFrame.
Series.drop_duplicates : Remove duplicate values from Series.

Examples
--------
By default, for each set of duplicated values, the first occurrence is
set on False and all others on True:

>>> animals = pd.Series(['lama', 'cow', 'lama', 'beetle', 'lama'])
>>> animals.duplicated()
0    False
1    False
2     True
3    False
4     True
dtype: bool

which is equivalent to

>>> animals.duplicated(keep='first')
0    False
1    False
2     True
3    False
4     True
dtype: bool

By using 'last', the last occurrence of each set of duplicated values
is set on False and all others on True:

>>> animals.duplicated(keep='last')
0     True
1    False
2     True
3    False
4    False
dtype: bool

By setting keep on ``False``, all duplicates are True:

>>> animals.duplicated(keep=False)
0     True
1    False
2     True
3    False
4     True
dtype: bool