code: def index_data(self, data: np.array):
      n = len(data)
      # indexing in batches is beneficial for many faiss index types
      logger.info("Indexing data, this may take a while.")
      self.index.train(data)
      self.index.add(data)
      logger.info("Total data indexed %d", n)
  
imports: import os
  import logging
  import pickle
  import faiss
  import numpy
label_desc: Use image node_id 2 for calling the DenseIVFFlatIndexer obj's underlying member method code with example usage: obj.index_data(data) without return types