User-callable function to create and return a unique temporary
directory. The return value is the pathname of the directory.
Arguments are as for mkstemp, except that the 'text' argument is
not accepted.
The directory is readable, writable, and searchable only by the
creating user.
Caller is responsible for deleting the directory when done with it.
3.5: suffix, prefix, and dir may now be supplied in bytes in order to obtain a bytes return value. Prior to this, only str was allowed. suffix and prefix now accept and default to None to cause an appropriate default value to be used.
3.6: The dir parameter now accepts a path-like object.
3.12: mkdtemp() now always returns an absolute path, even if dir is relative.