code: def user_set_avatar(self, action=None, quick_key=None, url=None):
          
          return self.request("user/set_avatar", QueryParams({
              "action": action,
              "quick_key": quick_key,
              "url": url
          }))
docs: user/set_avatar
  
          http://www.mediafire.com/developers/core_api/1.3/user/#set_avatar