Ansible custom module - DIY Missing pre-requisite

The documentation for Ansible module development says the prerequistes are:
build-essential libssl-dev libffi-dev python-dev
I’m on Open SUSE and these packages do not exist [all of them!]

Do you know where I can get them from? [for Open SUSE]

Do I need the python module virtualenv?
Or is this for local testing?

This is the doco I’m referring to:
https://docs.ansible.com/ansible/2.5/dev_guide/developing_modules_general.html

Version 2.5 is ancient in Ansible years. The top of that document says, “You are reading an unmaintained version of the Ansible documentation. Unmaintained Ansible versions can contain unfixed security vulnerabilities (CVE). Please upgrade to a maintained version. See the latest Ansible documentation.”

You should probably be starting from Developing modules.