The documentation for NamedTemporaryFile is a bit vague. It says

[--] That name can be retrieved from the name attribute of the file object. [--] The returned object is always a file-like object whose file
attribute is the underlying true file object. This file-like object can be used in a with statement, just like a normal file.

That `file-like object` vs `true file object` made me assume that I need to do

    f = NamedTemporaryFile()
    f.file.name

to get the filename, which sort of worked, but only later realized that `f.file.name` is actually the file descriptor number on Linux, a.k.a an integer. Thus I suggest that the one sentence be changed to "That name can be retrieved from the name attribute of the returned file-like object."