From what I was able to find, it’s defined in the following files:
[root@deploy ~]# grep -rl ALLOWED_CONTENT_CHECKSUMS /usr/lib/python3.6/site-packages/ | grep -v pyc
/usr/lib/python3.6/site-packages/pulpcore/app/models/content.py
/usr/lib/python3.6/site-packages/pulpcore/app/settings.py
/usr/lib/python3.6/site-packages/pulpcore/tests/functional/api/test_crd_artifacts.py
/usr/lib/python3.6/site-packages/pulp_2to3_migration/app/settings.py
/usr/lib/python3.6/site-packages/pulp_rpm/app/serializers/repository.py
/usr/lib/python3.6/site-packages/pulp_rpm/app/tasks/publishing.py
/usr/lib/python3.6/site-packages/pulp_rpm/app/constants.py
/usr/lib/python3.6/site-packages/pulp_rpm/tests/functional/api/test_publish.py
However, I tried editing a few of the files in which the array with the different checksums is defined, but I could not make Pulp process the puppet6 repo…