grasshopper sub-routine possible?

Due to the size of my project, my gh file is getting too big and difficult to manage...

I am wondering if there is a way to make a subroutine in rhino grasshopper.

Instead of having a large gh file, is it possible to have a mother gh file and several children gh files to be called in the mother file as in other programming/ scripts.

For example, let's suppose I have a gh file that makes an extrusion with a selected profile. Then, instead of copying and pasting the script into a new file, is there any way to call the file for the extrusion within the new file that has other functions.

Thanks!