I have a Python library which works in a specific field, created to simulate several astronomical behaviours. This library it was made by my teacher, and now I've made another module with a new class inside. Is it necessary to do something to install this new module? I use Jupyter Notebook to run my scripts and I used spyder to make it. I'm new with programming and I need help.

I tried to bring this module inside library directory, where are all modules that I usually use, and so I import class inside it in a Jupyter Notebook as other classes. For example:

from modul_A import class_A

from myModul import myClass

modul_A and myModul are in the same directory, but first import work and second import doesn't work. Can you help me?