old_contents: 
  import re
  from typing import Any, List, Text
  
  from rasa_nlu.components import Component
  from rasa_nlu.config import RasaNLUModelConfig
  from rasa_nlu.tokenizers import Tokenizer, Token
  from rasa_nlu.training_data import Message
  from rasa_nlu.training_data import TrainingData
  
  
  class WhitespaceTokenizer(Tokenizer, Component):
      name = "tokenizer_whitespace"
  
      provides = ["tokens"]
  
      def train(self, training_data, config, **kwargs):
          # type: (TrainingData, RasaNLUModelConfig, **Any) -> None
  
          for example in training_data.training_examples:
              example.set("tokens", self.tokenize(example.text))
  
      def process(self, message, **kwargs):
          # type: (Message, **Any) -> None
  
          message.set("tokens", self.tokenize(message.text))
  
      def tokenize(self, text):
          # type: (Text) -> List[Token]
  
          # there is space or end of string after punctuation
          # because we do not want to replace 10.000 with 10 000
          words = re.sub(r'[.,!?]+(\s|$)', ' ', text).split()
  
          running_offset = 0
          tokens = []
          for word in words:
              word_offset = text.index(word, running_offset)
              word_len = len(word)
              running_offset = word_offset + word_len
              tokens.append(Token(word, word_offset))
          return tokens
  
new_contents: import re
  from typing import Any, List, Text
  
  from rasa_nlu.components import Component
  from rasa_nlu.config import RasaNLUModelConfig
  from rasa_nlu.tokenizers import Tokenizer, Token
  from rasa_nlu.training_data import Message
  from rasa_nlu.training_data import TrainingData
  
  
  class WhitespaceTokenizer(Tokenizer, Component):
      name = "tokenizer_whitespace"
  
      provides = ["tokens"]
  
      def train(self, training_data, config, **kwargs):
          # type: (TrainingData, RasaNLUModelConfig, **Any) -> None
  
          for example in training_data.training_examples:
              example.set("tokens", self.tokenize(example.text))
  
      def process(self, message, **kwargs):
          # type: (Message, **Any) -> None
  
          message.set("tokens", self.tokenize(message.text))
  
      def tokenize(self, text):
          # type: (Text) -> List[Token]
  
          # there is space or end of string after punctuation
          # because we do not want to replace 10.000 with 10 000
          words = re.sub(r'[.,!?]+(\s|$)', ' ', text).split()
  
          running_offset = 0
          tokens = []
          for word in words:
              word_offset = text.index(word, running_offset)
              word_len = len(word)
              running_offset = word_offset + word_len
              tokens.append(Token(word, word_offset))
          return tokens
  
subject: Update rasa_nlu/tokenizers/whitespace_tokenizer.py