Advised to run if you do not want anyone accidentally updating Ubuntu; which will corrupt NVIDIA drivers or install conflicting packages.

Command

sudo sed -i 's/Prompt=.*/Prompt=never/' /etc/update-manager/release-upgrades

It is the same as editing /etc/update-manager/release-upgrades to 'prompt=never'.

Found from this thread: https://askubuntu.com/questions/1059971/disable-updates-from-command-line-in-ubuntu-16-04

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