how do i access ec2_facts inside a template?

cluster_info.md.j2

Your Cluster
===

You can access MCS at these addresses:
{% for webserver in groups['webserver'] %}
  {%- if 'ansible_ec2_public_hostname' in ec2_facts.ansible_facts -%}
* https://{{hostvars[webserver].ec2_facts.ansible_facts.ansible_ec2_public_hostname}}:8443
  {%- else %}
* https://{{hostvars[webserver].ec2_facts.ansible_facts.ansible_ec2_local_ipv4}}:8443
  {%- endif %}

  {% if not loop.last %}
or
  {% endif %}

{% endfor %}

playbook.yml

# register ec2 facts for host/group webserver. 
# write a file containing some stuff.

- hosts: webserver
  tasks:
    - name: get ec2 facts
      ec2_facts:
      register: ec2_facts
      when: '"instance_id" in hostvars[inventory_hostname]'

    - name: write some cluster info out
      local_action: template src=cluster_info.md.j2 dest=/tmp/cluster_info.md