[docs] do not tell users to delete /usr/bin/python3

[shiptux]

Problem

Section 3.2.1 of documentation/2.quick-start/quick_start_qemu/quick_start_qemu_linux.md instructs the reader to run:

sudo rm -rf /usr/bin/python3
sudo rm -rf /usr/bin/python
sudo ln -s /usr/bin/python3.9 /usr/bin/python3
sudo ln -s /usr/bin/python3.9 /usr/bin/python

On Debian and Ubuntu, apt and much of the system tooling are Python programs resolved through /usr/bin/python3, so following the guide leaves the machine unable to install packages at all — including the packages needed to undo it. The hardcoded 3.9 version also goes stale with every release.

Change

• Replace the manual removal/symlinking with python-is-python3, which is how these distributions provide the python command
• Add an explicit warning against the manual approach
• Drop the now-unreferenced screenshot

[github-actions]

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[github-actions]

📌 Code Review Assignment

🏷️ Tag: documentation

Reviewers: @CXSforHPU @GorrayLi @lianux-mm

Changed Files (Click to expand)

• documentation/2.quick-start/quick_start_qemu/figures/python3-version.png
• documentation/2.quick-start/quick_start_qemu/quick_start_qemu_linux.md

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📊 Current Review Status (Last Updated: 2026-09-08 22:11 CST)

• ⌛ @CXSforHPU Pending Review
• ⌛ @GorrayLi Pending Review
• ⌛ @lianux-mm Pending Review

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