a python script which asks you for login and ask any other email_id . it downloads all attachments of inbox came from that other email_id It will not download an attachment if it already exists in folder
To run this , you need pyhton3
It uses imaplib (https://docs.python.org/3.5/library/imaplib.html) and email (https://docs.python.org/3/library/email.html)
Also to use this you will have to enable imap after logging in google nd give permission to less secure apps(https://myaccount.google.com/lesssecureapps)