you seemed to have not yet a fundamental basic understanding of which program does what.
The Arduino-IDE is for writing code in a human-readable language: C++
Then the arduino-IDE translates this C++-code into assembler-code which readable by the microcontroller.
python is a programming-language that is supposed to run on computers not on microcontrollers.
python for computers (that run an OS like windows, linux, IOS) has no hardware-specific functions like switching IO-pins.
If you would like to write code with python that is able to switch IO-pins etc. you would have to use micropython which has these special functions for switching IO-pins etc.
Python is an interpreted language which is slower than a compiled language like C++ and the interpreter needs extra RAM.
So on something as small as a Arduino-Uno C++ is better suited.
If you can give an overview about what your robot-arm shall do all in all and how you want to control this robotarm all in all better suggestions can be made.
best regards Stefan