code: def test_description_basic(df):
      res = Description(df)
      assert isinstance(res.frame, pd.DataFrame)
      assert isinstance(res.numeric, pd.DataFrame)
      assert isinstance(res.categorical, pd.DataFrame)
      assert isinstance(res.summary(), SimpleTable)
      assert isinstance(res.summary().as_text(), str)
      assert "Descriptive" in str(res)
  
      res = Description(df.a)
      assert isinstance(res.frame, pd.DataFrame)
      assert isinstance(res.numeric, pd.DataFrame)
      assert isinstance(res.categorical, pd.DataFrame)
      assert isinstance(res.summary(), SimpleTable)
      assert isinstance(res.summary().as_text(), str)
      assert "Descriptive" in str(res)
  
      res = Description(df.b)
      assert isinstance(res.frame, pd.DataFrame)
      assert isinstance(res.numeric, pd.DataFrame)
      assert isinstance(res.categorical, pd.DataFrame)
      assert isinstance(res.summary(), SimpleTable)
      assert isinstance(res.summary().as_text(), str)
      assert "Descriptive" in str(res)
  
file_path: statsmodels/statsmodels/stats/tests/test_descriptivestats.py
imports: import numpy
  from numpy.testing import assert_almost_equal, assert_equal
  import pandas
  import scipy.stats
  import pytest
  from statsmodels.iolib.table import SimpleTable
  from statsmodels.stats.descriptivestats import Description, describe, sign_test
label_desc: Use image node_id 4 for calling a global function with example usage: test_description_basic(df) without return types