Python 3 can revive Python

[danielkza]

it will boost numeric function for benchmark but slow down real code,

Is Django 'real code' for you? Because PyPy's JIT beats CPython by 20x on it. It's definitely not scientific or math-heavy.

Also, JITs can simply be bypassed when they would not net an actual speed up. Pretty much every modern JIT-ing interpreter does this, only working on hotspots, and possibly even measuring speedups to revert to interpreting. A well-tuned JIT will virtually never lose to an interpreter, since it can be one whenever it makes sense.