def insert_before_node(self, node: Node, node_to_insert: Node) -> None:
        node_to_insert.next = node
        node_to_insert.previous = node.previous

        if node.get_previous() is None:
            self.head = node_to_insert
        else:
            node.previous.next = node_to_insert

        node.previous = node_to_insert