import glob
from PIL import Image
import numpy as np

image_list = []

for filename in glob.glob(r'E:\PyCharmProjects\Practice\mozaika\*.jpg'):
    im=Image.open(filename)
    im.thumbnail((100,100))
    image_list.append(im)

new_image = Image.new('RGB', (500, 500))

for image in image_list:
    for i in range(0, 500, 100):
        for j in range(0, 500, 100):
            new_image.paste(image, (i,j))
new_image.save('mozaika.jpg')