Is it possible to send Whatsapp message without Twilio or similar?

can this be done?

i.e. send a message to Whatsapp (or similar SM service) with python via the Panywhere website but without having to sign up to a third party such as Twilio?

Twilio is probably the best way to go for Whatsapp. I've played around with doing it without Twilio but it's a pain in the butt. On the other hand, Telegram has a much more open / welcoming setup- it would be possible to do that without Twilio.

ok, I might try Telegram as i use that regularly anyway

Another recommendation for Telegram here -- I use it to control all of my home automation stuff (we can send messages like "living room lights on" to a bot) and also one of our internal test systems that makes sure that always-on tasks are running OK is actually a Telegram bot that pings us every hour.

We have a simple tutorial for Telegram bots on PythonAnywhere here