code: def test_atom_features_only_atom_num():
      """
      Test for atom_features() when only_atom_num is True
      """
      smiles = "C"
      m = Chem.MolFromSmiles(smiles)
      atom = m.GetAtoms()[0]
      features = atom_features(atom, only_atom_num=True)
      req_f = list(np.zeros((133,), dtype=int))
      req_f[5] = 1
      assert len(features) == len(req_f)
      assert features == req_f
  
file_path: deepchem/deepchem/feat/tests/test_atom_feature_generator_dmpnn.py
imports: from deepchem.feat.molecule_featurizers.dmpnn_featurizer import get_atomic_num_one_hot, get_atom_chiral_tag_one_hot, get_atom_mass, atom_features, GraphConvConstants
  from rdkit import Chem
  import pytest
  import numpy
label_desc: Use image node_id 4 for calling a global function with example usage: test_atom_features_only_atom_num() without return types