def _is_symlink(file_info):
    """
    Check the upper 4 bits of the external attribute for a symlink.
    See: https://unix.stackexchange.com/questions/14705/the-zip-formats-external-file-attribute

    Parameters
    ----------
    file_info : zipfile.ZipInfo
        The ZipInfo for a ZipFile

    Returns
    -------
    bool
        A response regarding whether the ZipInfo defines a symlink or not.
    """
    return file_info.external_attr >> 28 == 10
