code: def lidstone_bigram_model(bigram_training_data, vocabulary):
      model = Lidstone(0.1, order=2, vocabulary=vocabulary)
      model.fit(bigram_training_data)
      return model
  
imports: import math
  from operator import itemgetter
  import pytest
  from nltk.lm import MLE, AbsoluteDiscountingInterpolated, KneserNeyInterpolated, Laplace, Lidstone, StupidBackoff, Vocabulary, WittenBellInterpolated
  from nltk.lm.preprocessing import padded_everygrams
label_desc: Use image node_id 13 for calling a global function with example usage: lidstone_bigram_model(bigram_training_data, vocabulary) and returns: model