Varnish, nginx, gunicorn, Django, redis, celery, postgres most of the time.
Sometime a bit of crossbar.io.
Laravel is a nice framework. I prefer it to symfony, espacially since they love Vue.js which is now my fav front end lib.
But the definitive advantage of using Python is that you get a much more versatile language than PHP. Python is not just good for the Web. It's heavily used for scripting, automation, sysadmin, data analysis, GUI, pentesting, etc.
People don't just use Python with HTTP in mind. You find it at Apple, NASA, at Sony, Fedora, in the state of Geneva, in french schools, in 3D (Maya, Blender) or geography (most GIS)...
Basically, you get a tool that you can use for a lot more stuff, because the ecosystem has been developed for a lot more types of tasks.