def _get_suffix(path):
    """
    Return suffix from `path`.

    ``/home/xex/somefile.txt`` --> ``txt``.

    Args:
        path (str): Full file path.

    Returns:
        str: Suffix.

    Raises:
        UserWarning: When ``/`` is detected in suffix.
    """
    suffix = os.path.basename(path).split(".")[-1]

    if "/" in suffix:
        raise UserWarning("Filename can't contain '/' in suffix (%s)!" % path)

    return suffix