This code is blowing my mind

I understand what the last three lines are supposed to do(update the pointers of the swapped nodes) I just don’t follow how. Maybe i need a break. I’m currently wired on coffee listening to aphex twin. S950tx16wasr10 [163.97] - YouTube

def swap_nodes(linked_list, val1, val2):
    node1 = linked_list.head_node
    node2 = linked_list.head_node
    node1_prev = None
    node2_prev = None

    while node1 != None:
        if node1.get_value() == val1:
        node1_prev = node1
        node1 = node1.get_next_node()

    while node2!= None:
        if node2.get_value() == val2:
        node2_prev = node2
        node2 = node2.get_next_node()

    if node1_prev == None:
        linked_list.head_node = node2

    if node2_prev == None:
        linked_list.head_node = node1

    temp = node1.get_next_node()

my brain is going to explode XD

Please post a link to the exercise page for more context.

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There are few moving parts, to be sure. If you have a white board, it might be helpful to sketch it out (or on a fresh sheet of paper).

As for the last swap, if we don’t update the pointers we end up with circular references and the linked list is corrupted.

The author uses the conventional array element swap…

temp = a
a = b
b = temp

Python lets us omit the temp variable…

a, b = b, a

effectively performs the swap, but that is beside the point.

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Thanks. Drawing it helped me understand !!

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