Is Python necessary for building physics simulations?

For someone like me who is interested in computational physics or building simulations from scratch(classical mechanics, EM, quantum etc.), should i delve deeper into python programming or should i try exploring matlab, c++ and other tools. I have seen many undergrad projects using python but when simulations become computationally heavy, should we still stick to python or write the performance critical part in c++?

Any insights would be greatly appreciated.