Has element?
    :param elem_ref:
    :return:

def has_elem(elem_ref):
    """
    Has element?
    :param elem_ref:
    :return:
    """
    if not is_elem_ref(elem_ref):
        return False
    elif elem_ref[0] == ElemRefObj:
        return hasattr(elem_ref[1], elem_ref[2])
    elif elem_ref[0] == ElemRefArr:
        return elem_ref[2] in elem_ref[1]