Means to view offline gmail backups with folders preserved and without a mail client


I was able to make an mbox backup of a personal gmail account as per here:
https://support.google.com/accounts/answer/3024190?hl=en

I used a program called mbox viewer which successfully imported the emails, but combined them all to one folder as shown below.

enter image description here

Is there a way to have the tag / folder information be recognized as separate folders in a gmail backup?