def get_dir_from_zipfile(zip_file, fallback=None):
    """Return the name of the root folder in a zip file.

    :param zip_file: a :class:`zipfile.ZipFile` instance.
    :param fallback: if `None`, the name of the zip file is used. This is
        returned if the zip file contains more than one top-level directory,
        or none at all.
    """
    fallback = fallback or zip_file.filename
    directories = [name for name in zip_file.namelist() if name.endswith("/")
                   and len(PurePath(name).parts) == 1]
    return fallback if len(directories) > 1 else directories[0]
def current_label(self) -> ProtocolLabel:
        if len(self.message.message_type) == 0:
            return None

        cur_label = self.message.message_type[self.current_label_index].get_copy()
        self.message.message_type[self.current_label_index] = cur_label
        cur_label.fuzz_values = [fv for fv in cur_label.fuzz_values if fv]  # Remove empty strings

        if len(cur_label.fuzz_values) == 0:
            cur_label.fuzz_values.append(self.message.plain_bits_str[cur_label.start:cur_label.end])
        return cur_label