Convert .png images into .jpg with python3

convert_png_to_jpg.py

import xml.etree.ElementTree as ET
import pickle
import os
from os import listdir, getcwd
from os.path import join
from PIL import Image

source_dir = "C:\\Users\\Lukas\\Desktop\\KITTI dataset\\left_camera\\VOC2012\\JPEGImages"
directory = os.fsencode(source_dir)

i = 0;
for file in os.listdir(directory):
    i = i + 1
    filename = os.fsdecode(file)
    print(i)
    im = Image.open(source_dir + "\\" + filename)
    rgb_im = im.convert('RGB')
    filename = filename[:-4]
    filename = filename + ".jpg"
    rgb_im.save('C:\\Users\\Lukas\\Desktop\\jpg_images\\' + filename)