code: def preprocess(img_file, input_name, output_name):
      with open(img_file, "rb") as file:
          image_data = file.read()
      image = cv2_to_base64(image_data)
      feed = {input_name: image}
      fetch = [output_name]
      return feed, fetch
  
file_path: PaddleSeg/test_tipc/serving_cpp/serving_client.py
imports: import sys
  import base64
  import io
  import argparse
  import numpy
  from PIL import Image
  from paddle_serving_client import Client
label_desc: Use image node_id 3 for calling a global function with example usage: preprocess(img_file, input_name, output_name) and returns: feed,  fetch