使用python将二维数组转化为双链表结构

rt，已经用递归方法完成，现要求利用循环完成转化，感觉无从下手

我研究了一下，写了个例子，实现了上下左右随意移动，就是不知道是否符合题意，你看看吧，

class FourWayNode():
    def __init__(self,data,up=None,down=None,previous=None,next=None):
        self.data = data
        self.next = next
        self.previous = previous
        self.up = up
        self.down = down

def constructDoublyLinkedListLoop(arr):
    nodeList = []
    for i in range(3) :
        v_node = [FourWayNode(j) for j in lst2d[i]]
        nodeList.append(v_node)

    for i in range(3) :
        for j in range(4):
            node = nodeList[i][j]
            if j==3:
                node.next = nodeList[i][0]
            else:
                node.next = nodeList[i][j+1]
            if j==0:
                node.previous = nodeList[i][3]
            else:
                node.previous = nodeList[i][j-1]
            if i==2:
                node.down = nodeList[0][j]
            else:
                node.down = nodeList[i+1][j]
            if i==0:
                node.up = nodeList[2][j]
            else:
                node.up = nodeList[i-1][j]
    head = nodeList[0][0]
    return head

lst2d = [[5,4,7,10],
         [6,12,1,9],
         [8,2,3,11]]

head = constructDoublyLinkedListLoop(lst2d)
print("--------------------------------")
print(head.data)
head = head.next
print(head.data)
head = head.down
print(head.data)
head = head.next
print(head.data)
head = head.down
print(head.data)
head = head.next
print(head.data)
head = head.up
print(head.data)
head = head.up
print(head.data)
head = head.previous
print(head.data)
head = head.previous
print(head.data)
head = head.previous
print(head.data)
print("--------------------------------")