This is good, as a developer is a PITA to follow all the dependencies your app have. There are several tools to keep them up to date (updating your requirements.txt file) for future builds/updates of your app. But sometimes we just don’t follow the security flaws.

GitHub’s Security Alerts now also work for Python projects, notifying developers about vulnerabilities in software packages that their projects depend on.

Source: GitHub adds Python support for security alerts – Help Net Security