code: def query(self, uri, delete=False):
      res_dict = self.db.hgetall(RESULT_PREFIX + self.name + ":" + uri)
  
      if not res_dict or len(res_dict) == 0:
          return "[]"
      if delete:
          self.db.delete(RESULT_PREFIX + self.name + ":" + uri)
      s = res_dict[b"value"].decode("utf-8")
      if s == "NaN":
          return s
      return self.get_ndarray_from_b64(s)
  
imports: import redis
  import time
  from zoo.serving.schema import *
  import httpx
  import json
  import uuid
label_desc: Use image node_id 4 for calling the OutputQueue obj's underlying member method code with example usage: obj.query(uri, delete) and returns: self, str, s