python humanize bytes

humanbytes.py

#Humanize byte size figures
def humanize_bytes(bytesize, precision=2):
    abbrevs = (
        (1<<50, 'PB'),
        (1<<40, 'TB'),
        (1<<30, 'GB'),
        (1<<20, 'MB'),
        (1<<10, 'kB'),
        (1, 'bytes')
    )
    if bytesize == 1:
        return '1 byte'
    for factor, suffix in abbrevs:
        if bytesize >= factor:
            break
    return '%.*f %s' % (precision, bytesize / factor, suffix)