How to get if key ==matches to get value, Please help on this.

[yuvaraj k]

Input json:

"ec2_asg": {
        "changed": false,
        "failed": false,
        "results": [

            { 

            "tags": [

                    {
                        "key": "peer_discovery_backend",
                        "propagate_at_launch": true,
                        "resource_id": "AnsibleASG",
                        "resource_type": "auto-scaling-group",
                        "value": "Rabbitmq"

                    }

]

} 

ec2_asg.yaml:
- name: Find a group with matching name/prefix and tags
      ec2_asg_info:
        name: "{{ AUTOSCALING_GROUP_NAME }}"
      register: ec2_asg


    - name: ASG Facts
      set_fact:
        PEER_DISCOVERY_BACKEND: "{{ec2_asg | json_query('ec2_asg.results[0].tags[0][?key=='peer_discovery_backend'].value') }}"

How to get the key matches and value return , i am getting error.

Thanks &Regards,

Yuvaraj K