I have a small graph 
.
I want to add nodes to a 2D list like this. 
0 is connected to nodes 1 and 2, so at index 0 these two nodes are inserted and so on. The program should take input from user. For simplification, I have written this code.
l = [[]]*4
l[0].append(1)
l[0].append(2)
l[1].append(0)
l[1].append(3)
l[2].append(0)
l[2].append(3)
l[3].append(1)
l[3].append(2)
print(l, end="\n")
But the output is
[[1, 2, 0, 3, 0, 3, 1, 2], [1, 2, 0, 3, 0, 3, 1, 2], [1, 2, 0, 3, 0, 3, 1, 2], [1, 2, 0, 3, 0, 3, 1, 2]]
And I want output as in the second image. How to achieve that?
