def set_write_bit(fn):
    if os.path.exists(fn):
        os.chmod(fn, (stat.S_IWRITE | stat.S_IWUSR))
    return
def set_write_bit(fn):
    if os.path.exists(fn):
        os.chmod(fn, (stat.S_IWRITE | stat.S_IWUSR))
    return