Once you’ve migrated code, update your classifiers in the setup.py file to contain Programming Language :: Python :: 3 to indicate your code supports Python 2 and 3. Make sure your code stays ...

For the hobby Python user, getting your code ready for Python 3 was often as simple as making sure your print() functions had the proper syntax. But migrating a huge library was another story.

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.