The following sentences look like a distraction to me:

« Additional quoting may be required because the entire string is a Python string.  It may be useful to use a Python raw string in complex cases. »

It is true of every string literal and is not specific to the subprocess module.

Also, I don't understand what the reference to "-c" is about. subprocess isn't only for executing Python interpreters. Or perhaps you are talking about "sh -c", but it is quite cryptic.