new_contents: #!/usr/bin/env python
  # -*- coding: utf-8 -*-
  """
      requests_cache.backends.mongo
      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  
      ``mongo`` cache backend
  """
  from requests_cache.backends.base import MemoryCache
  from requests_cache.backends.mongodict import MongoDict, MongoPickleDict
  
  # TODO: reusable connection
  class MongoCache(MemoryCache):
      """ ``mongo`` cache backend.
      """
      def __init__(self, db_name='requests-cache'):
          """
          :param db_name: database name (default: ``'requests-cache'``)
          """
          super(MongoCache, self).__init__()
          self.responses = MongoPickleDict(db_name, 'responses')
          self.url_map = MongoDict(db_name, 'urls')
  
  
subject: Add missed mongo.py