If you are running Mysql 5.7 and would like to upgrade it to Mysql 8, here is a guide that actually WORKS for Ubuntu 18.04
wget https://repo.mysql.com//mysql-apt-config_0.8.10-1_all.deb
sudo dpkg -i mysql-apt-config_0.8.10-1_all.deb
Choose mysql server and select mysql 8.0
sudo apt-get update
sudo apt-get install mysql-server
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