Did removing python3 break my Ubuntu?

I wanted to upgrade my python3 (3.5.x) on my Ubuntu 16.04 LTS to Python 3.6. As a first step, I apt-get remove‘d python3. I am sure I broke my Ubuntu update-alternatives: using /etc/mysql/my.cnf.fallback to provide /etc/mysql/my.cnf (my.cnf) in auto mode Removing apparmor (2.10.95-0ubuntu2.11) … Removing apport-gtk (2.20.1-0ubuntu2.21) … Removing apport (2.20.1-0ubuntu2.21) … Removing apt-xapian-index (0.47ubuntu8.4)…

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