code: def test_no_unnamed_index(all_parsers):
      parser = all_parsers
      data = """ id c0 c1 c2
  0 1 0 a b
  1 2 0 c d
  2 2 2 e f
  """
      result = parser.read_csv(StringIO(data), sep=" ")
      expected = DataFrame(
          [
              [0, 1, 0, "a", "b"],
              [1, 2, 0, "c", "d"],
              [2, 2, 2, "e", "f"],
          ],
          columns=["Unnamed: 0", "id", "c0", "c1", "c2"],
      )
      tm.assert_frame_equal(result, expected)
  
file_path: pandas/pandas/tests/io/parser/common/test_index.py
imports: from datetime import datetime
  from io import StringIO
  import os
  import pytest
  from pandas import DataFrame, Index, MultiIndex
  import pandas._testing
label_desc: Use image node_id 5 for calling a global function with example usage: test_no_unnamed_index(all_parsers) without return types