code: def get_productivity_stats(self):
          
          response = API.get_productivity_stats(self.api_token)
          _fail_if_contains_errors(response)
          return response.json()
docs: Return the user's productivity stats.
  
          :return: A JSON-encoded representation of the user's productivity
              stats.
          :rtype: A JSON-encoded object.
  
          >>> from pytodoist import todoist
          >>> user = todoist.login('john.doe@gmail.com', 'password')
          >>> stats = user.get_productivity_stats()
          >>> print(stats)
          {"karma_last_update": 50.0, "karma_trend": "up", ... }