code: def test_is_duplicated_df() -> None:
      df = pl.DataFrame({"foo": [1, 2, 2], "bar": [6, 7, 7]})
      assert_series_equal(
          df.is_duplicated(), pl.Series("", [False, True, True])
      )
  
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 7 for calling a global function with example usage: test_is_duplicated_df() without return types