It is an issue if you use `__annotations__` directly and you are using PEP 563's `from __future__ import annotations`. This currently gives some strings that may or may not refer to existing globals. With Larry's PEP 649 it will raise an error.
> Please note that this is a thread about PEP 649.
>
> If PEP 649 accepted and PEP 563 dies, all such idioms breaks
annotation completely.
>
> Users need to import all heavy modules and circular references used
only type hints, or user can not get even string form annotation which
is very useful for REPLs.
I don't see why `if TYPE_CHECKING:` idiom breaks annotations with PEP 649. There will be no error as long as `__annotations__` descriptor is not called.
And currently in 3.9 (with or without `from __future__ import annotations`), the issue is the same: you `get_type_hints` fails if some of the types in the annotations have been imported in a `if TYPE_CHECKING:` block.
> Hm, that's a rather serious problem with Larry's PEP 649 compared to from
__future__ import annotations, actually.
As I've written above, this is not a new issue, and neither this PEP nor PEP 563 can fix it.
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