code: def read_data_file(data_file_path):
      with open(data_file_path, "rb") as file:
          original = file.read()
      return original
  
file_path: BigDL/python/ppml/src/bigdl/ppml/kms/ehsm/file_operator.py
imports: from key_manager import retrieve_data_key_plaintext
  from cryptography.fernet import Fernet
  import os, csv, io
label_desc: Use image node_id 1 for calling a global function with example usage: read_data_file(data_file_path) and returns: original