docstr: Binary file objects should work (if 'mode' contains a 'b') or even without
  it in most cases.
  
  GH 35058 and GH 19827
docstr_tok: ["Binary","file","objects","should","work","(","if","'mode","'","contains","a","'","b","'",")","or","even","without","it","in","most","cases",".","GH","35058","and","GH","19827"]
code: def test_to_csv_binary_handle(self, mode):
      """
      Binary file objects should work (if 'mode' contains a 'b') or even without
      it in most cases.
  
      GH 35058 and GH 19827
      """
      df = DataFrame(
          1.1 * np.arange(120).reshape((30, 4)),
          columns=Index(list("ABCD")),
          index=Index([f"i-{i}" for i in range(30)]),
      )
      with tm.ensure_clean() as path:
          with open(path, mode="w+b") as handle:
              df.to_csv(handle, mode=mode)
          tm.assert_frame_equal(df, pd.read_csv(path, index_col=0))
  
imports: import io
  import os
  import sys
  from zipfile import ZipFile
  from _csv import Error
  import numpy
  import pytest
  import pandas
  from pandas import DataFrame, Index, compat
  import pandas._testing
label_desc: Use image node_id 34 for calling the TestToCSV obj's underlying member method code with example usage: obj.test_to_csv_binary_handle(mode) without return types