Clone the source code to all the VMs that you want to test. There are many ways to do it efficiently. One way is to use sshpass.
sshpass -p "password" rsync -a /your_directory_name address_of_vmStart by launching the script with python Talker.py on each of the VM.
One machine will be the introducer. The address of introducer can be configured in Util.py
In the beginning, the daemon will ask you to select a heart-beating style gossip or all-to-all, select unknown if you want that daemon to follow the style of other machines in the network.
The heart-beating style can be switched without exiting the process. Type either gossip or alltoall, then the style of all the VMs will be switched seamlessly to the new type you just entered.
You can choose to terminate the process by Ctr+C or typing leave in the program.