#variable file
interfaces_ipv4:
 - name: ens34
   bootproto: static
   ipaddress: 10.0.0.100
   netmask: 255.0.0.0
   onboot: yes

#template.j2  file
BOOTPROTO={{item.bootproto}}
{% if item.bootproto == static %}
IPADDR={{item.ipaddress}}
{% endif %}
NETMASK={{item.netmask}}
{% if item.gateway is defined %}
GATEWAY={{item.gateway}}
{% endif %}

#playbook
  template:
    src=/playbooks/roles/template/tasks/template.j2
    dest=/etc/sysconfig/network-scripts/ifcfg-{{item.name}}
  with_items:
    - "{{ interfaces_ipv4 }}"
  tags:
     - network_config
#Error when running
fatal: [192.168.211.142] => {'msg': "One or more undefined variables: 'static' is undefined", 'failed': True}
fatal: [192.168.211.142] => {'msg': 'One or more items failed.', 'failed': True, 'changed': False, 'results': [{'msg': "One or more undefined variables: 'static' is undefined", 'failed': True}]}

FATAL: all hosts have already failed -- aborting