The thing that function annotation syntax is good for is the ability to catch errors before they hit your production server at 2AM on a Tuesday. If you can des

The thing that function annotation syntax is good for is the ability to catch errors before they hit your production server at 2AM on a Tuesday. If you can describe the types that a function accepts and returns, violations of those rules can be caught by static analysis such as pylint and let you know before you commit. The current approach in Python after refactoring a large chunk of code is to grep through all the existing callers, fix what you can find, run the tests and hope for the best.