code: def test_dataframe_dir():
      df = DataFrame(
          pd.DataFrame(np.random.rand(4, 3), columns=list("ABC"))
      )
      dir_result = set(dir(df))
      for c in df.dtypes.index:
          assert c in dir_result
  
file_path: mars/mars/dataframe/tests/test_core.py
imports: import numpy
  import pandas
  import pytest
  from ...core import tile
  from ...lib.groupby_wrapper import wrapped_groupby
  from ...utils import pd_release_version
  from ..None import cut
  from ..initializer import DataFrame, Series, Index
label_desc: Use image node_id 6 for calling a global function with example usage: test_dataframe_dir() without return types