code: def register_domain(self, domain=0, tokenizer=None, trie=None):
          
          self.domains[domain] = IntentDeterminationEngine(
              tokenizer=tokenizer, trie=trie)
docs: Register a domain with the intent engine.
  
          Args:
              tokenizer(tokenizer): The tokenizer you wish to use.
              trie(Trie): the Trie() you wish to use.
              domain(str): a string representing the domain you wish to add