code: def test_add_hydrogens_to_mol(self):
      current_dir = os.path.dirname(os.path.realpath(__file__))
      ligand_file = os.path.join(
          current_dir, "../../dock/tests/1jld_ligand.sdf"
      )
      xyz, mol = rdkit_utils.load_molecule(
          ligand_file, calc_charges=False, add_hydrogens=False
      )
      original_hydrogen_count = 0
      for atom_idx in range(mol.GetNumAtoms()):
          atom = mol.GetAtoms()[atom_idx]
          if atom.GetAtomicNum() == 1:
              original_hydrogen_count += 1
  
      assert mol is not None
      mol = rdkit_utils.add_hydrogens_to_mol(mol, is_protein=False)
      assert mol is not None
      after_hydrogen_count = 0
      for atom_idx in range(mol.GetNumAtoms()):
          atom = mol.GetAtoms()[atom_idx]
          if atom.GetAtomicNum() == 1:
              after_hydrogen_count += 1
      assert after_hydrogen_count >= original_hydrogen_count
  
imports: import tempfile
  import unittest
  import os
  import numpy
  from deepchem.utils import rdkit_utils
label_desc: Use image node_id 5 for calling the TestRdkitUtil obj's underlying member method code with example usage: obj.test_add_hydrogens_to_mol() without return types