Hello there!
With my Python and REST API integration experience, I can confidently say that I'm the perfect candidate for the job and will complete this bot in the shortest delay and master it to perfection.
I suggest a web app with Django or Flask in the backend would do the job nicely, but we can always go for a normal script if that doesn't suit you. I'll let you know how we should tackle things once we get in touch. I'll be looking through the Mailman API documentation in the meanwhile.
Looking forward to hearing from you soon,
Best regards,
Abderrahmane Hana