Crossing the Python 3 Rubicon

Targeted at engineers that want to make the switch to Python 3, but don't know exactly where to start. The talk will introduce best practices that were already used at various companies, and I'll emphasize the strategies that we use successfully at Zapier to move a big Python codebase to Python 3. I'll present how to approach the migration starting from two main questions, what needs to be changed and how to change the codebase to work on both versions, while the migration is ongoing. We'll see in action tools such as `pylint` that can be used for getting incompatibility warnings between the two versions, we'll see how running the tests with `python -bb` and `python -3` could also spot tricky differences, and we'll also see in action tools such as `python-futurize` and `modernize` for automating the boring parts of a migration. At the end of this talk, the key takeaways will be a guideline that anyone could enforce for their projects for making the switch to Python 3, starting from the boring parts of a migration to the subtle parts where the semantics of the two versions are different.