> Serhiy Storchaka added the comment:
>
>> +        tmp_fileurl = 'file://localhost' + tmp_file
>
>         tmp_fileurl = 'file://localhost/' + tmp_file.replace(os.path.sep, '/')

Ok, I realized the mistake. 'file://localhost' + tmpfile is getting
expanded to 'file://localhostc:\something\..'
Yeah, the final '/' missing was the problem.

tmp_file.replace(...) is be better too, initial unwrap was encoding /
and  url2pathname to //. replacing path sep with '/' would be better.

Thanks for the suggestion, Serhiy.