def _get_last_td(el):
    """
    Return last <td> found in `el` DOM.

    Args:
        el (obj): :class:`dhtmlparser.HTMLElement` instance.

    Returns:
        obj: HTMLElement instance if found, or None if there are no <td> tags.
    """
    if not el:
        return None

    if type(el) in [list, tuple, set]:
        el = el[0]

    last = el.find("td")

    if not last:
        return None

    return last[-1]