def _nl_list_add(obj, prev, next_):
    """https://github.com/thom311/libnl/blob/libnl3_2_25/include/netlink/list.h#L27.

    Positional arguments:
    obj -- nl_list_head class instance.
    prev -- nl_list_head class instance.
    next_ -- nl_list_head class instance.
    """
    prev.next_ = obj
    obj.prev = prev
    next_.prev = obj
    obj.next_ = next_