old_contents: 
  from .WordTokenizer import WordTokenizer
  from .SentenceTokenizer import SentenceTokenizer
  from .PeykareReader import PeykareReader
  from .BijankhanReader import BijankhanReader
  from .HamshahriReader import HamshahriReader
  from .VerbValencyReader import VerbValencyReader
  from .DadeganReader import DadeganReader
  from .TreebankReader import TreebankReader
  from .Normalizer import Normalizer
  from .Stemmer import Stemmer
  from .Lemmatizer import Lemmatizer
  from .SequenceTagger import SequenceTagger, IOBTagger
  from .POSTagger import POSTagger, StanfordPOSTagger
  from .Chunker import Chunker, RuleBasedChunker
  from .DependencyParser import DependencyParser
  
  
  def sent_tokenize(text):
  	if not hasattr(sent_tokenize, 'tokenizer'):
  		sent_tokenize.tokenizer = SentenceTokenizer()
  	return sent_tokenize.tokenizer.tokenize(text)
  
  
  def word_tokenize(sentence):
  	if not hasattr(word_tokenize, 'tokenizer'):
  		word_tokenize.tokenizer = WordTokenizer()
  	return word_tokenize.tokenizer.tokenize(sentence)
  
new_contents: 
  from .WordTokenizer import WordTokenizer
  from .SentenceTokenizer import SentenceTokenizer
  from .PeykareReader import PeykareReader
  from .BijankhanReader import BijankhanReader
  from .HamshahriReader import HamshahriReader
  from .VerbValencyReader import VerbValencyReader
  from .DadeganReader import DadeganReader
  from .TreebankReader import TreebankReader
  from .Normalizer import Normalizer
  from .Stemmer import Stemmer
  from .Lemmatizer import Lemmatizer
  from .SequenceTagger import SequenceTagger, IOBTagger
  from .POSTagger import SequencePOSTagger, POSTagger
  from .Chunker import Chunker, RuleBasedChunker
  from .DependencyParser import DependencyParser
  
  
  def sent_tokenize(text):
  	if not hasattr(sent_tokenize, 'tokenizer'):
  		sent_tokenize.tokenizer = SentenceTokenizer()
  	return sent_tokenize.tokenizer.tokenize(text)
  
  
  def word_tokenize(sentence):
  	if not hasattr(word_tokenize, 'tokenizer'):
  		word_tokenize.tokenizer = WordTokenizer()
  	return word_tokenize.tokenizer.tokenize(sentence)
  
subject: fix import issue