--- 
- 
  connection: local
  gather_facts: false
  hosts: localhost
  tasks: 
    - 
      ec2: 
        count: 3
        image: ami-0cca6df87334a74bd
        instance_tags: 
          type: webinar
          system: example
          third_tag: 3
        instance_type: t2.micro
        key_name: webinar
        wait: true
      name: "create machine"
      register: ec2

    -
      name: run ssh-keyscan to add keys to known_hosts
      local_action: shell ssh-keyscan {{ item.public_ip }} >> ~/.ssh/known_hosts
      with_items: "{{ ec2.instances }}"