sorting a 2d list in python code example

Example 1: python order 2d array by secode element

sorted(arr, key=lambda x: x[1])

Example 2: how to create 2d list in python

o=[]
for i in range(0,rows):
    x=[]
    for j in range(0,cols):
        x.append(0)
    o.append(x)
#if you use [[0]*cols]*rows all rows will become the same list
#so editing in one row will edit all rows