Switch the Python shebang to use Python3 on XS 8.4 as well, remove Python 2 tests

[bernhardkaindl]

Switch from using Python 2.7 to Python 3.6 on XenServer 8.4:

• Switch the Python shebang to use Python 3.6 on XS 8.4
  • XS9 only has Python 3.11 (and bugtool has run on XS9 since February 2024)
• Update pyproject.toml from >=2.7 to >=3.6
• Update README.md
• Update doc/pre-commit.md
• Remove the Python 2 tests
• Convert the Container-based tests to use Python 3

Reviewer's Guide

File-Level Changes

Change	Details	Files
Switches script entrypoint to Python 3	Replaced shebang with “#!/usr/bin/env python3”	xen-bugtool
Updates documentation to drop Python 2 support and explain the migration	Rewrote FAQ sections to remove Python2 details Added stability/test coverage notes for Python 3 Outlined implementation steps for the Python3 switch	README.md doc/pre-commit.md
Removed Python 2 test runs in CI	Removed Python2 job from GitHub Actions workflow	.github/workflows/ci.yml

How stable and well-tested is the Python3 support in xen-bugtool?

• It is completely stable and well-tested on XS9:
  • The last Python3 issue was fixed on 25 March 2024, and since then, there have been no further Python3 issues.
• The test suite runs with very high code coverage on both Python 2 and Python 3 and is run on every commit by GitHub Actions.

Is Python 2 support still needed?

No. As regular support for XenServer 8.2 has ended, and there are no plans to backport big changes to XenServer 8.2, Python 2 support is no longer needed.

Why was Python 2 support kept for so long?

In the case of backporting complex changes to XenServer 8.2, using Python 2 on XenServer 8.4 provided confidence that Python 2 support was still functioning.

But this aspect is no longer a concern since the end-of-life of XS 8.2.

What are the benefits of dropping Python 2 support?

• Switching xen-bugtool to Python3 on XenServer 8.4 too should de-risk it from
  breaking its Python2 support accidentally when making changes to xen-bugtool:

• As developers now use Python3, the risk of accidentally breaking Python2 support
  exists. With Python 2 support dropped, this risk is gone.

• Also, more friendly Python3 features become available:

  • contextlib context manager suppress instead of try-except or try-finally.
  • f-strings instead of the older % formatting and "str1" + "str1", etc.
  • pathlib instead of os.path
  • Type annotations that can use type aliases for better readability

[Copilot]

Pull Request Overview

This PR transitions the xen-bugtool project from supporting both Python 2.7 and Python 3 to Python 3.6+ only, targeting deployment on XenServer 8.4 and later versions.

Key changes:

• Updates the main script shebang to use Python 3
• Removes Python 2 test infrastructure from CI workflows
• Updates project configuration and documentation to reflect Python 3.6+ requirement

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
xen-bugtool	Changed shebang from python to python3
tests/integration/xenserver-config-systemd.sh	Updated default Python version and removed Python 2 references
tests/integration/sar-file-collection.test.sh	Updated default Python version and fixed typo
pyproject.toml	Updated Python version requirement from >=2.7 to >=3.6 with exclusions
doc/pre-commit.md	Updated documentation to reflect Python 3 focus
README.md	Rewrote FAQ sections to explain Python 3 migration and benefits
.github/workflows/main.yml	Removed Python 2 test job and updated container tests to use Python 3

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[Copilot]

Pull Request Overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

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[Copilot]

Pull Request Overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

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[bernhardkaindl]

Split into PRs 157, 158, 159, and 160