Identity v3
Create new region
os region create
    [--parent-region <region-id>]
    [--description <description>]
    <region-id>
Parent region ID
New region description
New region ID
Delete region(s)
os region delete
    <region-id> [<region-id> ...]
Region ID(s) to delete
List regions
os region list
    [--parent-region <region-id>]
Filter by parent region ID