resort badly organized mp3s with a python script that generates a .bat or .sh that does the actual resorting

resortmp3.py

#!/usr/bin/env python
# encoding: utf-8 

#py.test --doctest-modules resortmp3.py

import sys
import re
import os
from collections import defaultdict
from numpy import base_repr
import subprocess

_fnencoding = sys.getfilesystemencoding()

tounknown='Downloads,artist,Artist,Interpret,interpret,Kein,kein,Unbekannt,unbekannt,Unknown,unknown'.split(',')
def tou(x):
    uk = 'unknown'
    for u in tounknown:
        if x.startswith(u):
            return uk
    if re.search('www\.',x):
        return uk
    rex=r'(\d+)\s+(.*)'
    if re.match(rex,x):
        x=re.sub(rex,r'\2',x)
    x=x.strip('_')
    if not x:
        return uk
    return x

fn=lambda x: '"'+os.path.normpath(x)+'"'

sofar=defaultdict(int)
def newdf(al,outdir=''):
    """
    >>> al = "downloads/vance joy  - first time.mp3"
    >>> newdf(al).replace('\\\\','/')
    'mkdir "downloads/vance joy" & move /Y "downloads/vance joy  - first time.mp3" "downloads/vance joy/first time.mp3"'

    >>> al="./Music/iTunes/iTunes Media/Music/Unbekannter Interpret/Unbekanntes Album (02.06.2007 12_23_46)/09 Titel 9.mp3"
    >>> newdf(al).replace('\\\\','/')
    'mkdir "unknown/unknown" & move /Y "Music/iTunes/iTunes Media/Music/Unbekannter Interpret/Unbekanntes Album (02.06.2007 12_23_46)/09 Titel 9.mp3" "unknown/unknown/09 Titel 9.mp3"'

    >>> al= "./Downloads/Our Endless Numbered Days (Full Album) By- Iron and Wine-2.mp3"
    >>> newdf(al).replace('\\\\','/')
    'mkdir "unknown/Our Endless Numbered Days (Full Album) By" & move /Y "Downloads/Our Endless Numbered Days (Full Album) By- Iron and Wine-2.mp3" "unknown/Our Endless Numbered Days (Full Album) By/Iron and Wine-2.mp3"'

    >>> al= "./Music/iTunes/iTunes Media/Music/3 Feet Smaller/3rd Strike/03 Strike back.mp3"
    >>> newdf(al).replace('\\\\','/')
    'mkdir "Feet Smaller/3rd Strike" & move /Y "Music/iTunes/iTunes Media/Music/3 Feet Smaller/3rd Strike/03 Strike back.mp3" "Feet Smaller/3rd Strike/03 Strike back.mp3"'

    >>> al="./Music/iTunes/iTunes Media/Music/Unknown Artist/Unknown Album/01 KC Taylor & Didier Vanelli - ElectroFuck - Remix Attack - Pacha Recordings.mp3"
    >>> newdf(al).replace('\\\\','/')
    'mkdir "ElectroFuck/Remix Attack" & move /Y "Music/iTunes/iTunes Media/Music/Unknown Artist/Unknown Album/01 KC Taylor & Didier Vanelli - ElectroFuck - Remix Attack - Pacha Recordings.mp3" "ElectroFuck/Remix Attack/Pacha Recordings.mp3"'

    >>> al= "Music/iTunes/iTunes Media/Music/Unknown Artist/Unknown Album/11 - Trouble.mp3"
    >>> newdf(al).replace('\\\\','/')
    'mkdir "unknown/unknown" & move /Y "Music/iTunes/iTunes Media/Music/Unknown Artist/Unknown Album/11 - Trouble.mp3" "unknown/unknown/Trouble.mp3"'

    >>> al= "Music/iTunes/iTunes Media/Music/Unknown Artist/Unknown Album/BEE GEES - The Very Best Of - 01 - New York mining disaster.mp3"
    >>> newdf(al).replace('\\\\','/')
    'mkdir "BEE GEES/The Very Best Of" & move /Y "Music/iTunes/iTunes Media/Music/Unknown Artist/Unknown Album/BEE GEES - The Very Best Of - 01 - New York mining disaster.mp3" "BEE GEES/The Very Best Of/New York mining disaster.mp3"'

    >>> al="Music/iTunes/iTunes Media/Music/Unknown Artist/Unknown Album/Andrew_Spencer_Dj_Gollum_-_In_The_Shadows_(DJ_Gollum_Mix)_www[1].technorocker.info.mp3"
    >>> newdf(al).replace('\\\\','/')
    'mkdir "unknown/unknown" & move /Y "Music/iTunes/iTunes Media/Music/Unknown Artist/Unknown Album/Andrew_Spencer_Dj_Gollum_-_In_The_Shadows_(DJ_Gollum_Mix)_www[1].technorocker.info.mp3" "unknown/unknown/Andrew_Spencer_Dj_Gollum_-_In_The_Shadows_(DJ_Gollum_Mix).mp3"'

    """
    global sofar
    ln_s=[xx for xx in [x.strip() for x in re.split(r'/|__|  |\s*-\s+',al)[-4:]] if re.sub('\d','',xx).strip()]
    ln_s=ln_s[-3:]
    d=[tou(ln_s[0]),tou(ln_s[1]),ln_s[2]]
    if 'www' in d[-1]:
        d[-1]=re.sub('(\w+)\s*www.*',r'\1',d[-1]).strip('_')+'.mp3'
    nd = os.sep.join(d[:2])
    nf = os.sep.join(d)
    sofar[nf]+=1
    if sofar[nf]>1:
       sofar[nd]+=1
       nd = os.path.join(nd+base_repr(sofar[nd],36))
       nf = os.path.join(nd,d[-1])
    nd = os.path.join(outdir,nd)
    nf = os.path.join(outdir,nf)
    if sys.platform=='win32':
        mv = 'mkdir {1} & move /Y {0} {2}'.format(
                fn(al)
                ,fn(nd)
                ,fn(nf)
                )
    else:
        mv = 'mkdir -p {1} & mv {0} {2}'.format(
                fn(al)
                ,fn(nd)
                ,fn(nf)
                )
    return mv

if __name__ == '__main__':
    assert len(sys.argv)==2, "provide output folder"

    po=subprocess.Popen(["find",".","-name","*.mp3"],stdout=subprocess.PIPE)
    lns=po.stdout.read().decode(encoding=_fnencoding).splitlines()

    if sys.platform=='win32':
        outfn = 'resortmp3.bat'
    else:
        outfn = 'resortmp3.sh'

    nedf = lambda x: newdf(x,outdir=sys.argv[1])

    with open(outfn,'w',encoding=_fnencoding) as f:
        f.write('\n'.join([nedf(al.strip()) for al in lns]))