TYP: Postponed Evaluation of Annotations (PEP 563)
a few files as POC/for discussion

from https://www.python.org/dev/peps/pep-0563/

> PEP 3107 added support for arbitrary annotations on parts of a function definition. Just like default values, annotations are evaluated at function definition time. This creates a number of issues for the type hinting use case:

> - forward references: when a type hint contains names that have not been defined yet, that definition needs to be expressed as a string literal;
> - type hints are executed at module import time, which is not computationally free.

> Postponing the evaluation of annotations solves both problems.