template with jinja2_native = False

{
  "vtc_config":{
    "vtc_data":"do_not_delete",
    "cli": "enable",
    "vdn_only":"0",
    "log_dir": "",
    "log_filter": "4",
    "log_master_only": "enabled",
    "walled_garden_check":"enabled",
    "domains":[
      {"name":"domain1",
        "dps_list":[
{% for host in groups['dps'] %}
          {"ip":"{{ hostvars[host].network[0].ipv4[0].ip }}","config_port":"{{ client_port }}"}{% if not loop.last %},{% endif %}{{ "\n" }}
{%- endfor %}
        ]
      }
    ]
  }
}

template with jinja2_native = True

{'vtc_config': {'cli': 'enable', 'log_filter': '4', 'vdn_only': '0', 'log_dir': '', 'walled_garden_check': 'enabled', 'domains': [{'name': 'domain1', 'dps_list': [{'ip': '192.168.2.10', 'config_port': '49001'}, {'ip': '192.168.2.20', 'config_port': '49001'}, {'ip': '192.168.2.30', 'config_port': '49001'}]}], 'vtc_data': 'do_not_delete', 'log_master_only': 'enabled'}}