force minimal temp file name

        dir_name = dir_name.strip()

        if not dir_name:

            continue

        # dir_name = _secure_filename(dir_name)  # why though ?

        dir_name = dir_name.strip()

        if dir_name:

            previous_dir, created = models.Collection.objects.get_or_create(

        total_chunks

    ):

        Path(lock_file_path).touch()  # lock dir

        f_name = "{}/{}".format(partials_dir, _secure_filename(file_name))

        f_name = "{}/upload_{}".format(partials_dir, _secure_filename(file_name))

        _join_parts(partials_dir, f_name, file_hash, total_chunks)

        with open(f_name, "rb") as f:

            try: