Python apps can now be configured using a '.python-version' file
Change effective on 14 October 2024
The Python version used by Python apps can now be specified using a .python-version file.
This file optionally supports specifying a Python version using only the major version (such as 3.13), which means that your app will use the latest Python patch version each time it builds - saving you from having to manually track new security updates.
The existing runtime.txt and Pipfile.lock Python version features will continue to work, however, we recommend switching to a .python-version file instead, since the .python-version file is more widely supported by other tooling in the Python ecosystem.
For more information, see our documentation on specifying a Python version.