old_contents: """
  Shared exception.
  """
  
  
  class BadRequestError(Exception):
      pass
  
  
  class ConflictError(Exception):
      pass
  
  
  class NotFoundError(Exception):
  
      def __init__(self, status_code=None):
          self.status_code = status_code
  
  
new_contents: """
  Shared exception.
  """
  
  
  class BadRequestError(Exception):
      pass
  
  
  class ConflictError(Exception):
      pass
  
  
  class NotFoundError(Exception):
  
      def __init__(self, status_code=None):
          super(NotFoundError, self).__init__()
          self.status_code = status_code
  
  
subject: Fix for pypy compatibility: must super's __init__