code: def make_ngrams_dicts(self):
      self.bigrams_dict, self.trigrams_dict = {}, {}
      bigram_combs = list(itertools.product(self.letters, self.letters))
      bigram_combs = ["".join(comb) for comb in bigram_combs]
      trigram_combs = list(
          itertools.product(self.letters, self.letters, self.letters)
      )
      trigram_combs = ["".join(comb) for comb in trigram_combs]
      for cnt, bigram in enumerate(bigram_combs):
          self.bigrams_dict[bigram] = cnt
      for cnt, trigram in enumerate(trigram_combs):
          self.trigrams_dict[trigram] = cnt + len(bigram_combs)
  
file_path: DeepPavlov/deeppavlov/models/entity_extraction/find_word.py
imports: import itertools
  import pickle
  from collections import Counter
  import numpy
  import scipy
  from deeppavlov.core.commands.utils import expand_path
label_desc: Use image node_id 3 for calling the WordSearcher obj's underlying member method code with example usage: obj.make_ngrams_dicts() without return types