formatting

      nodes = np.concatenate([nodes, master_atom_features], axis=0)

    # Get bond lists with reverse edges included

    edge_list = [(b.GetBeginAtomIdx(), b.GetEndAtomIdx())

                 for b in mol.GetBonds()]

    edge_list = [

      (b.GetBeginAtomIdx(), b.GetEndAtomIdx()) for b in mol.GetBonds()

    ]

    # Get canonical adjacency list

    canon_adj_list = [[] for mol_id in range(len(nodes))]