[Tutor] subprocess.call list vs. str argument

[Danny Yoo]

There are a few issues there.  I'd also recommend not trying to
shell-quote these manually,

    # in the argument list of os.subprocess:
    r'-H', '"%s"' % title,
    r'-A', '"%s"' % author,
    r'-V', '"%s"' % version,


Rather, just do the simpler thing:

    r'-H', title,
    r'-A', author,
    r'-V', version,

in conjunction with passing the "shell=False" keyword argument.  Don't
escape.  Just pass the arguments as is.


As far as I can tell, trying to do shell escaping is not only
unnecessary here, but doing without it makes the code cleaner safer.
Maybe there's another reason why Albert-Jan's situation is different
enough that "shell=True" is necessary, but the default situation
should be to avoid it.