Inventories
Here are four inventories to amuse you; two with just hostnames and two with variables added in to spice it up a little.
You can verify any of them as valid inventories with
ansible-inventory
and its graph
option.
An example command line is...
ansible-inventory --graph -i hosts.ini
Inventory variables
If you want to see the inventory variables too, you
will need to add --vars
to the command line.