Ive been learning Python for a while now and i feel confident in my abillity to use it.

But i dont feel like i can call myself a Python Developer.

is there a place to take some standardised test or smth to get a real "score"?

Not something that is widely accepted as proof of knowledge but rather smth to know if i know most of the language by now,

Perhaps start using LeetCode? It's what most cs grads use to train for interviews and stuff, it will test you on basic but fundamental stuff like data structures.

Start contributing to projects written in python on github. Plenty have issues that need to be fixed, they're a good challenge and a good reality check.