help me with this libraries

[snippsat]

Could you plz. be more specific, Im not good at python coding!

You need to talk with your teacher to get the file that used for this import.
I have look in the PDF posted,no code for LoadAtom and Atom.
What you missing is a file called Classes.py that i guess contain two classes LoadAtom and Atom.

Same with this import.

from Petersson_Hellsing import BuildAtomicMatrice

So this is a file from T Petersson and B Hellsing,which you probably know who is when study in this field.