new_contents: #! /usr/bin/env python
  # coding:utf-8
  
  import re
  
  
  class Preprocess:
  
      def __init__(self):
          self.html_regex = re.compile(
              r'(http|https)://[a-zA-Z0-9-./"#$%&\':?=_]+')
          self.newline_regex = re.compile(r'\n')
          self.cont_spaces_regex = re.compile(r'\s+')
  
      def _subs(self, regex: "re obj", repl: str, text: str):
          return regex.sub(repl, text)
  
      def remove_link(self, text: str) -> str:
          return self._subs(self.html_regex, "", text)
  
      def remove_newline(self, text: str) -> str:
          return self._subs(self.newline_regex, "", text)
  
      def remove_spaces(self, text: str) -> str:
          return self._subs(self.cont_spaces_regex, "", text)
  
      def convert_cont_spaces(self, text: str) -> str:
          return self._subs(self.cont_spaces_regex, " ", text)
  
      def strip(self, text: str) -> str:
          return text.strip()
  
      def execute(self, text: str) -> str:
          funcs = [
              self.remove_newline,
              self.remove_link,
              self.convert_cont_spaces,
              self.strip]
          _text = text
          for func in funcs:
              _text = func(_text)
          return _text
  
  
  class Twitter(Preprocess):
  
      def __init__(self):
          Preprocess.__init__(self)
          username = r'@[a-zA-Z0-9_]+'
          tag = r'#[a-zA-Z0-9_]+'
          self.mention_regex = re.compile(r'{}'.format(username))
          self.retweet_regex = re.compile(r'RT {}:'.format(username))
          self.tag_regex = re.compile(r'{}'.format(tag))
  
      def remove_mention(self, text: str) -> str:
          return self._subs(self.mention_regex, "", text)
  
      def remove_retweet(self, text: str) -> str:
          return self._subs(self.retweet_regex, "", text)
  
      def remove_tag(self, text: str) -> str:
          return self._subs(self.tag_regex, "", text)
  
      def execute(self, text: str) -> str:
          funcs = [
              self.remove_newline,
              self.remove_link,
              self.remove_retweet,
              self.remove_mention,
              self.remove_tag,
              self.convert_cont_spaces,
              self.strip]
          _text = text
  
          for func in funcs:
              _text = func(_text)
  
          return _text
  
  
  if __name__ == '__main__':
      import sys
  
      pre = Preprocess()
  
      for filename in sys.argv[1:]:
          print(filename)
          with open(filename, "r") as f:
              for line in f:
                  _line = line.strip()
                  print(pre.execute(_line))
  
subject: Add preprocessing.py