Here's how to find the IP address of a specific network interface that matches a given CIDR:
```yaml
- hosts: all
gather_facts: false
tasks:
- set_fact:
prod_ip_addr: "{{ item }}"
when: "item | ipaddr('192.168.10.0/24')"
with_items: "{{ ansible_all_ipv4_addresses }}"
- debug: var=prod_ip_addr
```
This is useful for example when you have a separate management network interface.
It's almost as easy as trying to explain what the script is doing in plain English.