Add example /usr/bin/env python as Python interpreter

[PierreBeucher]

I was looking for a way to use Python interpreter from an environment variable or directly from PATH rather than specifying absolute path as ansible_python_interpreter. For instance, I'm creating NixOS instance in Cloud and path to Python is hard to know in advance, I'd rather use the one from PATH.

Found out via ansible/ansible#6345 (comment) one could use

ansible_python_interpreter: '/usr/bin/env python'

And though it would be worth adding an example in doc :)

[gotmax23]

Thanks for your Ansible docs contribution! We talk about Ansible documentation on matrix at #docs:ansible.im and on libera IRC at #ansible-docs if you ever want to join us and chat about the docs! We meet there on Tuesdays (see the Ansible calendar) and welcome additions to our weekly agenda items - scroll down to find the upcoming agenda and add a comment to put something new on that agenda.

[gotmax23]

I''m not sure python_3_support.rst is the right place for this note. Interpreter discovery has its own doc. This point isn't specifically related to python3.

[PierreBeucher]

I looked around a bit before adding an example here as it also contains other example usage of ansible_python_interpreter. Why would the sub-section Using Python 3 on the managed machines with commands and playbooks not be suitable? It's related to using a specific Python interpreter for a managed machine.

Another candidate would be https://docs.ansible.com/ansible/latest/reference_appendices/interpreter_discovery.html but it clearly references the Python 3 support page for ansible_python_interpreter, hence putting it here.

What would you think is a better page for this? I can update MR accordingly

[oraNod]

@PierreBeucher Thanks for the docs contribution. I added a comment with some minor wording suggestions. As far as where this should go in the docs, my 2c is that it might fit ok after the last sentence in reference_appendices/interpreter_discovery.html. It is a bit tricky to find the best spot though. 😄

[PierreBeucher]

added a comment with some minor wording suggestions.

Thanks, I updated with your proposed change.

How about a seealso:: to python_3_support.rst from interpreter_discovery.rst for details and example about ansible_python_interpreter ? (it already exists the other way around so I guess it makes sense) This way all ansible_python_interpreter examples can be found at the same place, it will be less confusing for users and both "good" places are used. I changed accordingly

[oraNod]

Pushed a commit to add a sphinx anchor for the Python 3 Support section. LGTM now. Thanks for the docs contribution @PierreBeucher

[PierreBeucher]

Thanks @oraNod @samccann ! Glad this contribution made its way in :)