Add JSON type hint

import types

import numpy as np

import multiprocessing

from typing import Iterable, Union

from typing import Iterable, Union, Dict, Any

logger = logging.getLogger(__name__)

JSON = Dict[str, Any]

def _featurize_complex(featurizer, mol_pdb_file, protein_pdb_file, log_message):

  logging.info(log_message)

  """

  def featurize(self, structures: Iterable[dict],

  def featurize(self, structures: Iterable[JSON],

                log_every_n: int = 1000) -> np.ndarray:

    """Calculate features for crystal structures.

    Parameters

    ----------

    structures: Iterable[dict]

    structures: Iterable[JSON]

      Iterable sequence of pymatgen structure dictionaries.

      Json-serializable dictionary representation of pymatgen.core.structure

      https://pymatgen.org/pymatgen.core.structure.html