Top parent was flagged and can't be seen now. But stock Python 2.7 code can be run under PyPy and it's very fast if speed is a concern. PyPy3 is in beta essentially so that's not a production-ready option if you're into Python3.
I'm a Python2 programmer who is making my "Python3 transition" over to Go. So I don't have much attachment to it, but Python code isn't slow. I'm moving because of the language leadership towards conservatism towards the language which is my philosophy rather than feature-creep and technical churn.
The CPython implementation is, and it's still always been fast enough for everything I've written, so the meme is slightly overblown as far as I'm concerned.
