Cannot cast enum to another

[sherpya]

I've changed an enum and I'm getting:

sqlalchemy.exc.ProgrammingError: (sqlalchemy.dialects.postgresql.asyncpg.ProgrammingError) <class 'asyncpg.exceptions.CannotCoerceError'>: cannot cast type first_enum to second_enum

the fix is simple, instead of using postgresql_using='first_enum::second', I've changed to postgresql_using='first_enum::VARCHAR::second_enum'