code: def get_smiles(self, idx):
      return self.vocab[idx]
  
file_path: DIG/dig/ggraph/method/JTVAE/fast_jtnn/vocab.py
imports: import rdkit
  import rdkit.Chem
  import copy
label_desc: Use image node_id 3 for calling the Vocab obj's underlying member method code with example usage: obj.get_smiles(idx) and returns: self