code: def test_is_duplicated_series() -> None:
      s = pl.Series("a", [1, 2, 2, 3])
      assert_series_equal(
          s.is_duplicated(), pl.Series("a", [False, True, True, False])
      )
  
file_path: polars/py-polars/tests/unit/operations/unique/test_is_unique.py
imports: import polars
  from polars.testing import assert_series_equal
label_desc: Use image node_id 6 for calling a global function with example usage: test_is_duplicated_series() without return types