TL;DR: As of today (2019), in Python 3.7+ you can turn this feature on using a "future" statement, from __future__ import annotations. (The behaviour enabled by from __future__ import annotations might become the default in future versions of Python, and was going to be made the default in Python 3.10. However, the change in 3.10 was reverted at the last minute, and now may not happen at all. Pyth