[chrisseaton]

No, we know how to optimise all these issues. They're solved, through a combination of online profiling, inline caching, splitting, deoptimisation, scalar replacement, etc. (I wrote a PhD on it.) I don't think you could name a single Python language feature that we don't know how to optimise efficiently. (I'd be interested if you could.) But implementing them all is a difficult engineering challenge, even for Google, mainly because it involves storing a lot of state in a system that isn't designed to have state attached everywhere.

[mixmastamyk]

Yes, that’s what my reply means, your “no…” is poor communication style. If you think you can do better than the folks working on it for a decade plus, by all means step up.

[chrisseaton]

But you can't actually give any examples? Ok.

I'll give you one you could have used - the GIL - however I'm not sure the GIL's semantics are really specified for Python, they're an implementation detail people accidentally have relied on.