This python script generates a GAP code that can be run with the polyhedral package for GAP. You can generate such a script for a Bell polytope by running:
python generate_adm_polyhedral.py 2 2 2 2
This creates a GAP script in the scripts directory. You can execute the resulting script by:
gap scripts/2222_polyhedral.g
Note that you need to install the polyhedral package before you can execute these scripts. You can find install instructions here.