Find duplicate mp3 files in a folder

DupeFinder.py

import os
import re
import hashlib

def tagAll(dirname):
    files = os.listdir(dirname)
    files = [x for x in files if not os.path.isdir(dirname + '/' + x)]
    tagged = {}
    dupes = []
    originals = []
    for f in files:
        f = dirname + '/' + f
        code = tag(f)
        if not code in tagged: 
            tagged[code] = f 
        else:              
            dupes.append({'file' : f, 'matches' : tagged[code]})
            originals.append(f)
    return {'originals': originals, 'dupes' : dupes }

def tag(filename):
    f = open(filename, 'r')
    f.read(16 * 8)
    raw = f.read(16**2).encode('base64')
    f.close()
    tag = hashlib.sha224(raw).hexdigest()
    return tag

"""
Change the following for your mp3 directory
"""
mp3s = '/Volumes/MyMp3s'

processed = tagAll(mp3s)

a,b = len(processed['originals']), len(processed['dupes'])

print 'originals   -> %i' % a
print 'duplicates  -> %i' % b
print 'total files -> %i' % (a + b)
for dup in processed['dupes']:
    print dup