What are type hints in Python 3.5?

Question

One of the most talked about features in Python 3.5 is type hints.

An example of type hints is mentioned in this article and this o

Answer 1

Adding to Jim's elaborate answer:

Check the typing module -- this module supports type hints as specified by PEP 484.

For example, the function below takes and returns values of type str and is annotated as follows:

def greeting(name: str) -> str:
    return 'Hello ' + name

The typing module also supports:

1. Type aliasing.
2. Type hinting for callback functions.
3. Generics - Abstract base classes have been extended to support subscription to denote expected types for container elements.
4. User-defined generic types - A user-defined class can be defined as a generic class.
5. Any type - Every type is a subtype of Any.