FreeCAD’s Python functions are all well organized in different modules. Some of them are already loaded (imported) when you start FreeCAD. Just try:

dir()

https://wiki.freecad.org/Python_scripting_tutorial

https://wiki.freecad.org/FreeCAD_Scripting_Basics

https://wiki.freecad.org/Python_console

https://wiki.freecad.org/Power_users_hub

https://wiki.freecad.org/Debugging#Python_Debugging

https://wiki.freecad.org/Profiling

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