The source of truth for these partitions is not that code. It's the endpoints.json released in botocore (and replicated into every other sdk):

https://github.com/boto/botocore/blob/a0e22400396eabd5a58e4b...

To quickly list all of them, you can use a simple jq expression, such as the following:

    curl https://raw.githubusercontent.com/boto/botocore/a0e22400/botocore/data/endpoints.json | jq '.partitions[] | [.partitionName, .partition, .regions]'