"from_type()" can now resolve "TypeVar" instances when the "bound" is
a "ForwardRef", so long as that name is in fact defined in the same
module as the typevar (no "TYPE_CHECKING" tricks, sorry). This feature
requires Python 3.7 or later.
Thanks to Zac Hatfield-Dodds and Nikita Sobolev for this feature!
The canonical version of these notes (with links) is on readthedocs.