code: def test_map_no_dtype_set_8531() -> None:
      df = pl.DataFrame({"a": [1]})
  
      result = df.with_columns(
          pl.col("a")
          .map_batches(lambda x: x * 2)
          .shift(n=0, fill_value=0)
      )
  
      expected = pl.DataFrame({"a": [2]})
      assert_frame_equal(result, expected)
  
file_path: polars/py-polars/tests/unit/operations/map/test_map_batches.py
imports: from __future__ import annotations
  from functools import reduce
  import numpy
  import pytest
  import polars
  from polars.testing import assert_frame_equal
label_desc: Use image node_id 2 for calling a global function with example usage: test_map_no_dtype_set_8531() without return types