Use register and with_items

[ioggstream]

Add this example

- hosts: localhost
  tasks:
  - name: List all possibile /etc/hosts candidates
    stat:
      path: >-
        {{item}}
    with_items:
    - /etc/FOO
    - /etc/hosts
    register: etc_hosts_candidates
  - name: Show only existing
    debug:
      msg: >
        {{ etc_hosts_candidates.results 
           | selectattr("stat.exists", "equalto", true) 
           | list }}

Get the first one. Remember map should go before first as it works on lists
and if you put it after, iiuc the item is implicitly converted into its keys which have no "item" attribute

- hosts: localhost
  gather_facts: no
  tasks:
  - stat:
      path: >-
        {{item}}
    with_items:
    - /etc/FOO
    - /etc/hosts
    register: o
  - debug:
      msg: >
        {{ o.results
          | selectattr("stat.exists", "equalto", true)
          | map(attribute="item")
          | first
         }}