portstat | A simple port traffic monitor | Proxy library

You can invoke the "stop" or "start" method in your foreach loop while iterating through the instances.

It looks to me like what you are looking for is what Ansible call handlers.

As we’ve mentioned, modules should be idempotent and can relay when they have made a change on the remote system. Playbooks recognize this and have a basic event system that can be used to respond to change.

These ‘notify’ actions are triggered at the end of each block of tasks in a play, and will only be triggered once even if notified by multiple different tasks.

For instance, multiple resources may indicate that apache needs to be restarted because they have changed a config file, but apache will only be bounced once to avoid unnecessary restarts.

Note that handlers are simply a pair of

1. A notify attribute on one or multiple tasks
2. A handler, with a name matching your above mentioned notify attribute

So your playbook should look like