Get CherryMusic album art filenames for directories

albumart.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""{script} [-r] [-f DIR] [-h|--help] [STARTDIR]

Get CherryMusic album art filenames for subdirectories.

-r             recursive lookup in subdirectories
-f DIR         find and print only this directory's art name
-h or --help   print this text and exit
"""
from __future__ import unicode_literals
from __future__ import print_function

import hashlib
import os
import sys

if sys.version_info < (3,):
    sys.argv = [a.decode('UTF-8') for a in sys.argv]
    __print = print
    def print(*args, **kwargs):
        enc = ((a.encode('UTF-8') if isinstance(a, unicode) else str(a)) for a in args)
        __print(*enc, **kwargs)

try:
    from shlex import quote
except ImportError:
    from pipes import quote

startdir = '.'
recurse = False
find = None
encoding = 'UTF-8'

script, args = sys.argv[0], sys.argv[1:]
USAGE = __doc__.format(script=script)

try:
    while args and args[0].startswith('-'):
        option = args.pop(0)
        if option == '-r':
            recurse = True
        elif option == '-f':
            find = args.pop(0) + ''
        elif option in ('-h', '--help'):
            print(USAGE)
            sys.exit(0)
        else:
            raise ValueError("Unknown option: " + repr(option))
    if args:
        startdir = args.pop(0) + ''
    if args:
        raise ValueError("Too many argument(s): " + ', '.join(args))
except Exception as e:
    print(str(e), USAGE, sep='\n', file=sys.stderr)
    sys.exit(1)
if not os.path.isdir(startdir):
    print('Directory not found:',  startdir, file=sys.stderr)
    sys.exit(1)

def md5ify(dirname):
    encoded_dirname = dirname.encode(encoding)
    hashed =  hashlib.md5(encoded_dirname).hexdigest()
    return hashed + '.thumb'

def dirnames():
    walkdir = os.path.abspath(startdir)
    prefixlen = len(walkdir.rstrip(os.path.sep) + os.path.sep)

    for dirpath, dirnames, filenames in os.walk(walkdir):
        reldir = dirpath[prefixlen:]
        for subdir in sorted(dirnames):
            dirname = os.path.join(reldir, subdir)
            if not find:
                yield dirname
            elif dirname == find:
                yield dirname
                return
        if not recurse:
            return

for dirname in dirnames():
    out = [quote(dirname), md5ify(dirname)]
    if find:
        out.pop(0)
        find = None
    print(*out, sep='\t')

if find:
    print('directory', quote(find), 'not found', file=sys.stderr)
    sys.exit(1)