[bibyte]

Implementing a minimal Python is pretty easy (even with the huge standard library) but implementing a complete Python implementation is a herculean task. And even after that there is no guarantee that every Python library will run on your implementation (Pypy).

I don't know about you but I would rather make hundreds of Scheme and Forth implementations then one Python interpreter. But I don't really see that as a downside. I mean who decides on a language based on how easy it is to implement ?

[patrec]

Well, all things being equal a cleaner and more understandable language is going to be easier to implement, so I don't think difficulty of implementation should be dismissed so easily. Especially when the difficulty of implementation is not due to advanced features such as a fast runtime, resumable exceptions, proper tail calls, multi-method dispatch, pattern matching, powerful concurrency abstractions, SMP...