Very interesting python development… drop in static typing.

The mypy programming language is an experimental Python variant that aims to combine the benefits of dynamic or “duck” typing and static typing. Our goal is to have the expressive power and convenience of Python combined with compile-time type checking. The long-term goal is to also support efficient compilation to native code, without the need of a heavy-weight VM.Mypy is still in development. The current prototype supports type checking and running programs using a standard Python VM, i.e. there is no performance boost yet development roadmap. A significant subset of Python features is supported.

via mypy – A New Python Variant with Dynamic and Static Typing.