arr = [[]]
arr[0].append('test')
print arr

arr = [[]]
arr[0].append('test')
arr[1].append('qwe2')
print arr

 
massive = []
for x in range(5):
    massive.append([])
    for y in range(5):
        massive[-1].append(x*y)
        
print massive[2][2]
print massive
massive = [[[],[],[],[],[]],[],[],[],[],[],[],[],[],[],[],[],[],[],[]]
print massive

4

[[0, 0, 0, 0, 0], [0, 1, 2, 3, 4], [0, 2, 4, 6, 8], [0, 3, 6, 9, 12], [0, 4, 8,
12, 16]]

[[[], [], [], [], []], [], [], [], [], [], [], [], [], [], [], [], [], [], []]

>>> matrix = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]

>>> matrix[1]
[4, 5, 6]
>>> matrix[1][1]
5
>>> matrix[2][0]
7