This book describes Python, an open-source general-purpose interpreted programming language available for the most popular operating systems. The current versions are 3.x while versions 2.x are no longer supported, since 2020. This book describes primarily the versions 3.x, but does at times reference versions 2.x.
There are a few implementations of Python 3 (all of which also support Python 2):
CPython, the standard implementation written in C.
PyPy, a JIT-compiled version written in RPython (a subset of Python).
IronPython, a C# implementation that runs on the .NET environment.
Nuitka, a Python 3 to C 11 transpiler.
Jython, a Java implementation is also available, however it only supports Python 2.
