A Transform node can do what can be done with pure Python 2.7 code.
The Python node can use the rest of the Python 2.7 libraries. The reason I'm saying this is I'm not exactly sure what you are asking, but went to ChatGPT to get an idea what you would need. It suggested using scipy which it says is not a "pure Python" library. It seems that it is available in Python 2.7 though, so you could use the Python node with it.

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Ernest Jones
Precisely Software Inc.
PEARL RIVER NY
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