def human_bytes(size):
    """Formats size, a number of bytes, in a human-readable way."""
    suffices = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB', 'HB']
    for suffix in suffices:
        if size < 1024:
            return "%3.1f %s" % (size, suffix)
        size /= 1024.0
    return "big"