Upgrade to Python 3.8

To provide additional features from Python 3.8 to our users, and since Python 3.7 will no longer receive security updates as of 2023-06-27, Colab has upgraded to Python 3.8 (with plans to upgrade to more modern versions in the future). Additionally, this upgrade provides benefits for the packages we pre-install in our runtime, as many can only be upgraded with a newer Python version.

Colab’s fallback runtime version

Using the fallback runtime version temporarily allows access to the last version of the runtime before the upgrade described above, and is available until mid-December. Its purpose is to provide a temporary mechanism for users to more smoothly upgrade their notebooks to be compatible with Colab’s current runtime version. This is available from the Command Palette via the "Use fallback runtime version" command when connected to a runtime. Of note, this setting does not persist across sessions – the command will need to be invoked on each new session.