new_contents: import pytest
  from nlp import *
  
  def test_rules():
  	assert Rules(A = "B C | D E") == {'A': [['B', 'C'], ['D', 'E']]}
  
  
  def test_lexicon():
  	assert Lexicon(Art = "the | a | an") == {'Art': ['the', 'a', 'an']}
  	
subject: Add tests for rules and lexicon in nlp.py (#212)