- Mux files together
  ``` python
  import os
  import subprocess
  import sys
  import glob
  import re
  import shutil
  
  ffmpeg_home:str = 'C:\\Users\\Monzi\\Desktop\\Portables\\ffmpeg-2021-01-01-git-63505fc60a-full_build\\bin'
  mkvtoolnix_home:str = 'C:\\Users\\Monzi\\Desktop\\Portables\\mkvtoolnix-64-bit-51.0.0\\mkvtoolnix'
  tmp_dir = 'C:\\tmp'
  
  video_source_dir = sys.argv[1]
  audio_source_dir = sys.argv[2]
  result_dir = sys.argv[3]
  
  
  def merge(video_source, audio_source, target):
  	tmp_target = os.path.join(tmp_dir, os.path.basename(video_file).replace('&','And'))
  	subprocess.call(
  		['ffmpeg.exe', '-i', video_source, '-i', audio_source, 
  	 	'-map', '0:v', '-map', '1:a', '-map', '0:a', '-map', '0:s', '-disposition:a:0', 'default', '-disposition:a:1', 'none', '-c', 'copy', 
  	 	tmp_target], shell = True, cwd=ffmpeg_home)
  
  	subprocess.call(
  		['mkvpropedit.exe', tmp_target, '--edit', 'track:s1', '--set', 'flag-default=0'], shell = True, cwd=mkvtoolnix_home)
  
  	shutil.move(tmp_target, target)
  	 
  
  def scan(dir):
  	for path in sorted(glob.glob(f'{dir}/*.[ma][kv][vi]')):
  		yield path
  
  def extract_episode(f):
  	return re.search(r"([sS][0-9]+[eE][0-9]+)", f).group(1)
  
  def match_episode(f1, f2):
  	episode_1 = extract_episode(f1)
  	episode_2 = extract_episode(f2)
  	if episode_1.lower() != episode_2.lower():
  		raise Exception(f'Episode mismatch {episode_1} - {episode_2}')
  
  
  video_files = list(scan(video_source_dir))
  audio_files = list(scan(audio_source_dir))
  l1 = len(video_files)
  l2 = len(audio_files)
  if l1 != l2:
  	raise Exception(f'Length mismatch: {l1} - {l2}')
  
  for video_file, audio_file in zip(video_files, audio_files):
  	match_episode(video_file, audio_file)
  	
  for video_file, audio_file in zip(video_files, audio_files):
  	target_file = os.path.join(result_dir, os.path.basename(video_file))
  
  	print('Merging: ' + video_file + ' ' + audio_file + ' -> ' + target_file)
  	merge(video_file, audio_file, target_file)
  ```