Solved by cc5b4cb40e77805f1eec in post #3 
              
              
                may be the for-loop is what you need… 
a = ([[40, 3], [41, 3], [30, 3], [31, 3]],
[[30, 3], [40, 3], [50, 3], [43, 5]],
[[12, 3], [30, 3], [31, 3], [17, 3], [27, 3]],
[[60, 4], [70, 4]])

for ele in a:
    for i in range(5-len(ele)):
        ele.append([0, 0])

print(a)

you will get 
([[40, 3], [41…