Conditionally executing jupyter-notebook with %run

I have a jupyter-notebook (in Microsoft Fabric) in which I define functions, imagine like this:

NOTEBOOK_1: CELL_1:

def add(int a, int b): return a + b 

Then I want to run this notebook in another one to access the function like this: NOTEBOOK_2: CELL_1:

%run NOTEBOOK_1 

CELL_2:

x, y = 5 print(add(x, y)) 

Since I have several notebooks like notebook 2 and run them in sometimes arbitrary order, I need access to the function at all times but want to skip running notebook 1 if the function is already defined. How can I do this?

I tried this: NOTEBOOK_1: CELL_0:

try: prep_source_metadata except NameError: print("Execution necessary. Proceeding...") else: print("Execution unnecessary. Exiting...") mssparkutils.notebook.exit(1) 

However, this also exits notebook 2 since there is no dedicated separate notebook run.

I also found this post, How to pass a variable to magic ´run´ function in IPython, where I insert a variable into the %run part. Since I wouldn't want an error, I suppose I would have to make an empty dummy notebook for the "don't run" version. That would work well enough, I guess, but would be totally unelegant. Is there a better way?

EDIT1: Regarding the comments (thanks!):

• Since I'm constrained by Microsoft Fabric, I can't just use a .py file, I have to work with notebooks.
• importnb is not finding the other notebook (might be due to the Microsoft Fabric framework...):

import importnb with importnb.Notebook(): from NOTEBOOK_2 import add 

leads to

Cell In[7], line 4 1 import importnb 3 with importnb.Notebook(): ----> 4 from Gold_Automation_Functions import prep_source_metadata ModuleNotFoundError: No module named 'Gold_Automation_Functions' 

• Running another Notebook with MSSparkUtils does not work because the namespace is not shared (or however you describe that correctly, it's "NameError: name 'my_function' is not defined")

Another thing I tried which doesn't work is exiting the called notebook with MSSparkUtils. That exits the calling notebook as well, unfortunately. Trying to skip all cells might be a worthwhile approach, but there doesn't seem to exist an easy, elegant solution either.

EDIT2: Most promising avenue so far seems to be using a .whl file (https://learn.microsoft.com/en-us/fabric/data-engineering/environment-manage-library).