code: def test_also_column_manipulation_no_change(dataframe):
      """Test that changed dataframe inside `.also()` doesn't get returned."""
      cols = tuple(dataframe.columns)
      df = dataframe.also(remove_first_two_letters_from_col_names)
      assert dataframe is df
      assert cols == tuple(df.columns)
  
file_path: pyjanitor/tests/functions/test_also.py
imports: from unittest.mock import Mock
  import pytest
label_desc: Use image node_id 4 for calling a global function with example usage: test_also_column_manipulation_no_change(dataframe) without return types