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Brute force would be (should be, maybe
sudo apt-get --allow-unauthenticated update
To get past the mysql issue
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 467B942D3A79BD29
And the INDI
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 487CEC2B3F33A288