converting video clips into GIF. Python

Hi,
I want a website/webapp which convert video clips from given video URL , into GIF
1.User can paste url ( video link) from any social media platform
2. our site will Load that video on site n then user can scroll n select the part they want to create as GIF.
3. Free version will have Watermark ( admin can upload PNG watermark)
4. Admin can set price for Paid version.
5. Admin can add paypal link to make payment.
6. GIF can be download as,or directly can be Shared to popular social media sites.


Thanks.