code: def nltk_tokenzier_factory(nltk_tokenizer):
  	'''
  	Parameters
  	----------
  	nltk_tokenizer : nltk.tokenize.* instance (e.g., nltk.TreebankWordTokenizer())
  
  	Returns
  	-------
  	Doc of tweets
  
  	Notes
  	-------
  	Requires NLTK to be installed
  	'''
  
  	def tokenize(text):
  		toks = []
  		for tok in nltk_tokenizer.tokenize(text):
  			if len(tok) > 0:
  				toks.append(Tok(_get_pos_tag(tok),
  				                tok.lower(),
  				                tok.lower(),
  				                ent_type='',
  				                tag=''))
  		return Doc([toks], text)
  
  	return tokenizf nltk_tokenzier_factory(nltk_tokenizer):
  	'''
  	Parameters
  	----------
  	nltk_tokenizer : nltk.tokenize.* instance (e.g., nltk.TreebankWordTokenizer())
  
  	Returns
  	-------
  	Doc of tweets
  
  	Notes
  	-------
  	Requires NLTK to be installed
  	'''
  
  	def tokenize(text):
  		toks = []
  		for tok in nltk_tokenizer.tokenize(text):
  			if len(tok) > 0:
  				toks.append(Tok(_get_pos_tag(tok),
  				                tok.lower(),
  				                tok.lower(),
  				                ent_type='',
  				                tag=''))
  		return Doc([toks], text)
  
  	return tokenize
docs: Parameters
  	----------
  	nltk_tokenizer : nltk.tokenize.* instance (e.g., nltk.TreebankWordTokenizer())
  
  	Returns
  	-------
  	Doc of tweets
  
  	Notes
  	-------
  	Requires NLTK to be installed