old_contents: from __future__ import (absolute_import, division,
                          print_function, unicode_literals)
  from builtins import *
  from enum import Enum
  
  
  class MimeType(Enum):
      APPLICATION_JSON = 'application/json'
      # type: str
  
  
  class HttpHeaders(Enum):
      CONTENT_TYPE = 'Content-Type'
      # type: str
  
  
new_contents: from __future__ import (absolute_import, division,
                          print_function, unicode_literals)
  from builtins import *
  from enum import Enum
  
  
  class MimeType(Enum):
      APPLICATION_JSON = 'application/json'
      # type: str
  
  
  class HttpHeaders(Enum):
      CONTENT_TYPE = 'Content-Type'
      # type: str
  
  
  
subject: Add newline at the EOF of constants.py