code: def get(self, id):
          
          try:
              if self.request.headers.get("Id"):
                  object_ = yield self.client.find_one({self.request.headers.get("Id"): id})
              else:
                  object_ = yield self.client.find_one_by_id(id)
  
              if object_:
                  self.write(object_)
                  return
  
              self.raise_error(404, "%s/%s not found" % (self.object_name, id))
  
          except InvalidId as ex:
              self.raise_error(400, message="Your ID is malformed: %s" % id)
          except Exception as ex:
              self.logger.error(ex)
              self.raise_error()
docs: Get an by object by unique identifier
  
          :id string id: the bson id of an object
          :rtype: JSON