For the Dependencies see requirements text or you can run the command:
> pip install -r requirements.txt
Need to be installed on the server machine for the chat app
If you work on linux you can search it on google
Or you can run the server using Docker, where you can run the bellow code to make instance and run it:
docker run --name=redis-devel --publish=6379:6379 --hostname=redis --restart=on-failure --detach redis:latest