Cannot find file keystonerc_admin in Red Hat OpenStack Platform

Issue

As per https://access.redhat.com/documentation/en/red-hat-openstack-platform/9/paged/integrate-with-identity-service/chapter-2-identity-management-integration

Section 2.8

1. Create a copy of the existing keystonerc_admin file:

This file does not exist anywhere on the filesystem of any of the controller nodes, it does not exist on the director node either.