code: def test_astype_string_copy_on_pickle_roundrip():
      # https://github.com/pandas-dev/pandas/issues/54654
      # ensure_string_array may alter array inplace
      base = Series(np.array([(1, 2), None, 1], dtype="object"))
      base_copy = pickle.loads(pickle.dumps(base))
      base_copy.astype(str)
      tm.assert_series_equal(base, base_copy)
  
imports: import pickle
  import numpy
  import pytest
  from pandas.compat.pyarrow import pa_version_under12p0
  import pandas
  from pandas import DataFrame, Series, Timestamp, date_range
  import pandas._testing
  from pandas.tests.copy_view.util import get_array
label_desc: Use image node_id 7 for calling a global function with example usage: test_astype_string_copy_on_pickle_roundrip() without return types