face_recognition | simplest facial recognition api for Python and the command line | Computer Vision library

This below code will generate face encodings using multiprocessing , i can able to print the encoding but the problem is the knownEncodings ,knownNames ,no_faces ,error_in_image all are empty after the execution. I know its due to multiprocessing , but not sure how to mitigate this.

import face_recognition
from imutils import paths
from multiprocessing import Pool
import pickle
import cv2
import os,sys,time

print("[INFO] quantifying faces...")

img_folder_path=sys.argv[1]

image_paths = list(paths.list_images(img_folder_path))

knownEncodings = []
knownNames = []
no_faces = []
error_in_image =[]

def create_encoding(imagePath):
    print("[INFO] processing image...")
    name = imagePath.split(os.path.sep)[-1]
    image = cv2.imread(imagePath)
    if image is None:
        return
    rgb = cv2.cvtColor(image, cv2.COLOR_BGR2RGB)

    # detect the (x, y)-coordinates of the bounding boxes
    # corresponding to each face in the input image
    boxes = face_recognition.face_locations(rgb)

    # compute the facial embedding for the face
    if len(boxes) != 0:
        boxes = list(boxes[0])
        encodings = face_recognition.face_encodings(image, [boxes])
        for encoding in encodings:  
            knownEncodings.append(encoding)
            knownNames.append(name)
        
    else:
        print("no face found" ,image_paths )
        no_faces.append(image_paths )



# loop over the image paths with multiprocessing
start_time = time.time()

with Pool(8) as pool:
    pool.map(create_encoding, image_paths )


end_time = time.time()
print(end_time - start_time)

# dump the facial encodings + names to disk
print("[INFO] serializing encodings...")
data = {"encodings": knownEncodings, "names": knownNames, "no_faces":no_faces,"error_in_image":error_in_image}

f_name = img_folder_path.replace("/","-")
print(f_name)
f = open(f"encodings_{f_name}.pickle", "wb")
f.write(pickle.dumps(data))
f.close()