PyPy is an implementation of the Python_ programming language written in
Python itself, flexible and easy to experiment with.  Our long-term goals are
to target a large variety of platforms, small and large, by providing a
compiler toolsuite that can produce custom Python versions.  Platform, memory
and threading models are to become aspects of the translation process - as
opposed to encoding low level details into the language implementation itself.
Eventually, dynamic optimization techniques - implemented as another
translation aspect - should become robust against language changes.

PyPy是一个用python本身编写的python语言实现，灵活且容易在它上面
实验。我们长期的目标是针对大范围的多种平台，不管小的大的，通过
提供一个编译器工具集来生产相应的python版本。平台、内存和线程模
型将作为转换过程中的方面－与之相反的是将底层细节编码到语言实现
本身中去。最终，动态优化技术－实现为另一个转换方面－应该当语言
变化时是完善的。

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