As I understand the article, the problem is that an employee machine is misconfigured and uses the public package repo for a private package. The package in que

As I understand the article, the problem is that an employee machine is misconfigured and uses the public package repo for a private package. The package in question seems to be explicitly pinned in the requirements.txt - that’s essentially a whitelist. Whitelisting also suffers from the issue that a good public packages could at any time turn into a malicious package - so you’d need to pin the version. A task that seems infeasible for developer machines at googles scale. Sandboxing the development environment could be done, but would only help against this attack if the sandbox cannot connect to the public internet- which again would be painful. Googles strategy of accepting that this kind of breach will happen and rather focus on mitigation of the resulting damage seems like the better way.