code: def test_list_flatten():
      ser = Series(
          [[1, 2, 3], [4, None], None],
          dtype=ArrowDtype(pa.list_(pa.int64())),
      )
      actual = ser.list.flatten()
      expected = Series(
          [1, 2, 3, 4, None], dtype=ArrowDtype(pa.int64())
      )
      tm.assert_series_equal(actual, expected)
  
file_path: pandas/pandas/tests/series/accessors/test_list_accessor.py
imports: import re
  import pytest
  from pandas import ArrowDtype, Series
  import pandas._testing
  from pandas.compat import pa_version_under11p0
label_desc: Use image node_id 4 for calling a global function with example usage: test_list_flatten() without return types