class_docstr: Static Faiss Retrieval Flask resource.
  The PUT method is to get KNN tokens.
code: def __init__(
      self,
      index,
      tokenizer,
      ds,
      query_bert_ip,
      query_bert_port,
  ):
      # server
      self.index = index
      self.tokenizer = tokenizer
      self.ds = ds
      self.query_bert_ip = query_bert_ip
      self.query_bert_port = query_bert_port
      self.chunk_size = ds.chunk_size
      pad_id = self.tokenizer.pad_id
      self.no_retrieval = (
          np.ones((1, 1, 2 * self.chunk_size), dtype=ds._index.dtype)
          * pad_id
      )
  
imports: import base64
  import logging
  import pickle
  import threading
  import time
  from typing import List, Union
  import faiss
  import numpy
  import torch
  from flask import Flask, jsonify, request
  from flask_restful import Api, Resource
  from nemo.collections.common.tokenizers.tokenizer_spec import TokenizerSpec
  from nemo.collections.nlp.data.language_modeling.megatron.indexed_retrieval_dataset import MMapRetrievalIndexedDataset
  from nemo.collections.nlp.modules.common.megatron.retrieval_services.util import lock, request_data
label_desc: Use image node_id 1 to create a new FaissRetrievalResource object from inherited base classes: Resource with example: obj = FaissRetrievalResource(index, tokenizer, ds, query_bert_ip, query_bert_port)