How to add roles in bulk in HCM/Finance SAAS 18C/19A

Summary

Need to add roles in bulk or take backup of user roles and update again for bulk users

Content

Hi,

In Saas HCM and Finance 19A or even 18C.IF we have say 50 users and i need the list of all the roles for the users 

1)To capture all the existing roles for the user,is there a report or table to query and get this ?

2)If I want to udpate say for example another 10 new roles for these 50 users,Is there an way to do it as a bulk load?instead of manually adding one by one to each user from security console.?