Since I mentioned one-liners, I will say that this is definitely one area where Perl outshines Python. Python technically can do one-liners but it's really not at all as capable as Perl would be in the same setting. Python's regular expression library is very good but it's annoying to write little scripts whenever you need to use it in the context in question. I used sed for the last instance where I needed a one-liner but sed isn't Turing-complete (that I know of—if it is, not in any way I want to use). awk is Turing-complete but much less capable than Perl otherwise.