code: def test_then_column_names(dataframe):
      df = dataframe.then(remove_first_two_letters_from_col_names)
      cols = tuple(df.columns)
      assert cols == (
          "",
          "ll__Chart",
          "corated-elephant",
          "imals@#$%^",
          "ties",
      )
  
imports: import pytest
label_desc: Use image node_id 3 for calling a global function with example usage: test_then_column_names(dataframe) without return types