> Or I could explicitly convert the memoryview to a bytes object.  That
> strikes me as rather preferable.  However, this defeats one use of
> memoryview, which is to avoid unnecessary copying.  So it might be
> suitable workaround for some cases, but not all.

Indeed, that's why I think it would be good to fix the bytes.join()
method (which is precisely meant to minimize copying and resizing).