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The language reference [1] says:
 Ultimately, the loader is what makes use of __file__ and/or __cached__
This implies that loaders should use __file__ and __cached__ when loading a module. Instead loaders are meant to implement exec_module() and use the spec that's passed in.
The entire section should have a clear note that loaders are not meant to rely a module's import-related attributes.
[1] https://docs.python.org/3/reference/import.html#__file__
[2] https://docs.python.org/3/reference/import.html#import-related-module-attributes 

Would it suffice to change
"Ultimately, the loader is what makes use of __file__ and/or __cached__"
to 
"Ultimately, the loader set the values of __file__ and/or __cached__"
?

> "Ultimately, the loader set the values of __file__ and/or __cached__"
Change it to "sets" and +1 from me!

The key point is that loaders should be using the spec, not any of the module attrs (like `__file__` and `__cached__`), nor setting them.
For the specific paragraph I referenced, it would look more like:
 It is also appropriate to set __cached__ when __file__ is not set.
 However, that scenario is quite atypical. Ultimately, __file__ and
 __cached__ are set by the import system from the module spec provided
 by the finder. The spec instructs the loader. If a loader can load
 from a cached module but otherwise does not load from a file, that
 atypical scenario may be appropriate.

If this is still open, I would like to work on this. Please let me know.

Hi Vidhya — @slateny submitted a PR for this issue only two days ago (you can see that it's linked to this BPO issue in the "Pull Requests" field). I think it would be good to wait until that has been reviewed before doing any work on a possible PR for this issue :)
If you'd like to help out with this issue, you'd of course be very welcome to submit a review for @slateny's patch.

Thanks Alex. I will look into @slateny's patch.