gistfile1.txt

instance_tags: 
    environment: sandbox
    github_username: jarv
    Name: jarv-sandbox


...

- name: Launch ec2 instance
  local_action:
    module: ec2
    keypair: "{{ keypair }}"
    group: "{{ security_group }}"
    instance_type: "{{ instance_type }}"
    image: "{{ ami }}"
    wait: true
    region: "{{ region }}"
    instance_tags: "{{instance_tags}}"

failed: [localhost] => {"failed": true, "item": ""}
msg: this module requires key=value arguments (['image=ami-5cbddc6c', 'instance_type=c1.xlarge', 'key_name=platform-ansible', 'region=us-west-2', 'group=ansible', 'count=1', 'wait=true', 'instance_tags=', "{'environment': 'sandbox', 'Name': 'jarv-sandbox', 'github_username': 'jarv'}"])