Add section about Python 3.12 prerequisite

From Epoxy, Python 3.12 is required for Ansible control host.

Author: seunghun1ee

doc/source/operations/upgrading-openstack.rst

@@ -353,6 +353,42 @@ After the queue migration is finished, upgrade RabbitMQ to 4.1.
 
       kayobe kolla ansible run "rabbitmq-upgrade 4.1"
 
+Python 3.12
+-----------
+
+From OpenStack 2025.1, Kayobe and Kolla-Ansible requires Python 3.12.
+
+Ubuntu 24.04 has default Python of version 3.12.
+You can find the upgrade procedure from :ref:`upgrading-to-ubuntu-noble`
+
+For Rocky Linux 9, install Python 3.12 manually.
+
+.. code-block:: bash
+
+   dnf install python3.12
+
+For both Operating Systems, Kayobe and Kolla-Ansible Python virtual environments
+created with older Python version will not work with OpenStack 2025.1.
+Create new Kayobe Python virtual environment with Python 3.12.
+
+.. code-block:: bash
+
+   # Ubuntu 24.04
+   python3 -m venv venvs/kayobe
+
+   # Rokcy Linux 9 need to specify python3.12 as it is not the default
+   python3.12 -m venv venvs/kayobe
+
+Activate Kayobe Python virtual environment then Install Kayobe.
+
+.. code-block:: bash
+
+   source venvs/kayobe/bin/activate
+   pip install -r $KAYOBE_CONFIG_PATH/../../requirements.txt
+
+Run ``kayobe control host bootstrap`` to populate Kolla-Ansible Python virtual
+environment and bootstrap Ansible control host.
+
 Preparation
 ===========