Terminal not opening up after upgrading python to 3.7

This way the upgrade to 3.7 is useless. You should edit the gnome-terminal file:

Open a terminal and issue the following commands:

cd /usr/bin
sudo nano gnome-terminal

Change #!/usr/bin/python3 to #!/usr/bin/python3.6.

This way you can still use the power of 3.7 and solve the issue with the terminal.

I ran the command

sudo update-alternatives --config python3

Entered 1

I got my terminal back.

Still wonder why it wasn't working with python3.7.1 though.

To get access to command line if terminal is not opening up try the below shortcuts to run commands on a virtual terminal or refer to how-to-access-bash-without-a-terminal-emulator

Ctrl+Alt+(F1 through F4 at least, maybe up to F6) run a terminal interface on the virtual consoles. Once there, to get back to the GUI, use Ctrl+Alt+F7.