code: def test_to_csv_dups_cols2(self):
      # GH3457
      df = DataFrame(
          np.ones((5, 3)),
          index=Index([f"i-{i}" for i in range(5)], name="foo"),
          columns=Index(["a", "a", "b"], dtype=object),
      )
  
      with tm.ensure_clean() as filename:
          df.to_csv(filename)
  
          # read_csv will rename the dups columns
          result = read_csv(filename, index_col=0)
          result = result.rename(columns={"a.1": "a"})
          tm.assert_frame_equal(result, df)
  
imports: import csv
  from io import StringIO
  import os
  import numpy
  import pytest
  from pandas.errors import ParserError
  import pandas
  from pandas import DataFrame, Index, MultiIndex, NaT, Series, Timestamp, date_range, period_range, read_csv, to_datetime
  import pandas._testing
  import pandas.core.common
  from pandas.io.common import get_handle
label_desc: Use image node_id 29 for calling the TestDataFrameToCSV obj's underlying member method code with example usage: obj.test_to_csv_dups_cols2() without return types