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2.7: The IronPython Component
IronPython is the DotNet version of Python. Being an open platform independent scripting language, Python comes with many useful libraries (of which however not all run under IronPython).
In order to use it from within Grasshopper under Rhino5 install GHPython which can be downloaded from Food4Rhino.
Grasshopper for Rhino6 and 7 comes with GHPython by default.