But, somebody will probably write a "lexsub" pragma that does away with the "no warnings ...", and portability becomes less of an issue over the course of time, much like I can nowadays treat the features of v5.10 as given.
Perl had nested functions since v5, just with akward syntax. Does Python have proper <del>variable declarations</del> closures? That is more of a dealbraker than non-experimental nested function syntax for me ;-)
I scare-quote "uninitialized" because what it really is is nonexistant, which isn't the same thing.
Python has had proper closures forever, just with awkward syntax. But there is nothing you can do with closures in Perl that I can't translate directly into Python code that does the exact same thing in the exact same way. (I may need to switch from a scalar to an array with 1 element so that modifications in a child scope are visible in the outer, but conceptually things remain the same.)
I'm not saying that you should use Python - I switch it up but Perl is my goto language - however you shouldn't spread incorrect rumors about Python.