from moviepy.editor import *
import os
from natsort import natsorted
L =[]
for root, dirs, files in os.walk("/path/to/the/files"):
#files.sort()
files = natsorted(files)
for file in files:
if os.path.splitext(file)[1] == '.mp4':
filePath = os.path.join(root, file)
video = VideoFileClip(filePath)
L.append(video)
final_clip = concatenate_videoclips(L)
final_clip.to_videofile("output.mp4", fps=24, remove_temp=False)