With 35 million lines of Python code, the Athena trading platform is at the core of JPMorgan's business operations. A late start to migrating to Python 3 could create a security risk.

But annotating four million lines of Python code in this way isn’t a straightforward task, here are some of the lesser-known benefits and how Dropbox accomplished the task.

Facebook-owned Instagram has detailed its solution to improving the app in a way that enhances Python's advantages and mitigates the language's obstacles to productivity in large-scale projects ...