Bulk Mailbox / Email Account Creator

So from time to time I have to bring over a customer from another host that isnt on cPanel. Unfortunately, such manual transfers are rather tedious. One part of these is having to recreate all mailboxes! I usually get a list of mailboxes with passwords and I have to sit recreating each one!

Would be great if cPanel had the ability to create mailboxes in bulk from a csv or even a formatted textarea field where you put the mailbox name with a space and then its password, each line depicting a new mailbox.

Even if this feature was only available on the WHM of the root and/or reseller instead of a client cPanel interface - that would help greatly.