I'm trying to fetch the names of host groups in Ansible that have a specific prefix. Right now, I'm trying to delegate a template task to servers under host groups with the prefix "config\_". 

I'm using `json_query` which uses JMESPath expressions. The query however is incorrect. Can anyone guess what I'm missing?

```
- name: Create configsvr config file   
  template: src=mongod.conf.j2 dest={{ mongod.conf.path }} owner=mongod group=mongod mode=0600
  delegate_to: "{{ groups|json_query([?starts_with(@, `config_`)]) }}" 

```

Error msg:

```
 FAILED! => {"failed": true, "msg": "template error while templating string: unexpected char u'?' at 22. String: {{ groups|json_query([?starts_with(@, `config_m`)]) }}"}

```