Proxy User Commands
Note: These commands are for account administrators only. 
    addproxyuser
Adds a user that you have created as a proxy for another user, with an expiration date (yyyy-mm-dd). You cannot create a proxy user for a user created by another Account Administrator.
Use thelistcreatedusers command to find out who you can add as a proxy
        user.addproxyuser username proxy_username expiration_date This example allows user1@company.com to proxy as user2@company.com:
addproxyuser user1@myco.com user2@myco.com 2016-06-31listproxyusers
Lists all proxy users that were added using addproxyuser. It does not list any of the implicit proxy users, the members of your account.
listproxyusers
    removeproxyuser
Drops a user as a proxy for another.
removeproxyuser username proxy_username