How to extract the grants on default roles of PostgreSQL 10: pg_read_all_settings, pg_read_all_stats, pg_monitor and pg_signal_backend?

I have a Postgres instance of version 10 running on AWS RDS. I have a user there with default roles granted to it. I want to create the same user on my sandbox where the instance is of version 9.4. Thus, I want to know the grants that are included in these default roles of version 10.