Segmentation from reference segment

Hello,
I’m looking to automate a somewhat complex manual segmentation and trimming process. I would like to explore all the available options for this. Specifically, I’m wondering if Slicer has a feature to segment based on a reference segment that has already been manually segmented.

Initially, I want to do this through the UI, but Eventually, I would like to implement the process through a Python script.

Could you provide more insight into how this could be achieved?

It is impossible to tell anything really useful without knowing anything about the structures you want to segment. With this much information all I can think of are 1) training a DL model for your needs or 2) Creating a generic initial seeding for Grow from seeds, adapting it to the current image and run GrowCut.

If you want better advice, I suggest providing more details.