code: def test_overwrite_df():
      data_path = os.path.join(
          os.path.dirname(__file__), "data", "3eiy.pdb"
      )
      pdb = PandasPdb().read_pdb(data_path)
  
      def overwrite():
          pdb.df = "bla"
  
      expect = (
          "Please use `PandasPdb._df = ... ` instead\n"
          "of `PandasPdb.df = ... ` if you are sure that\n"
          "you want to overwrite the `df` attribute."
      )
  
      assert_raises(AttributeError, expect, overwrite)
  
imports: from biopandas.pdb import PandasPdb
  from biopandas.testutils import assert_raises
  import os
label_desc: Use image node_id 1 for calling a global function with example usage: test_overwrite_df() without return types