I'm trying to update to v18.0, but I keep getting these errors telling me there is an update trying to happen on module names but it already exists and so the upgrade fails. How is this not being checked? I go into psql to delete that module and I try to run upgrade again, but then its a different module the error is coming from. 

psycopg2.errors.UniqueViolation: duplicate key value violates unique constraint "ir_module_module_name_uniq"

DETAIL:  Key (name)=(l10n_uk_bacs) already exists.

Is there a known fix for this?