Remove unnecessary imports and lines

import re

import numpy as np

from collections import defaultdict

from typing import DefaultDict, Union, List

from typing import DefaultDict, Union

from deepchem.utils.typing import PymatgenComposition

from deepchem.feat import MaterialCompositionFeaturizer

    'Pb', 'Bi', 'Ac', 'Th', 'Pa', 'U', 'Np', 'Pu'

]

formulare = re.compile(r'([A-Z][a-z]*)(\d*\.*\d*)')

class CompositionFeaturizer(MaterialCompositionFeaturizer):

  """