[0]
(0,1)
[[0,1],[2,3]]
[(0,1),(2,3)]
[(0,1),(2,3)]
([0,1],(2,3),[4],(5,'a'),6,'b')
[0,1]
(0,1)
[[0,1],[2,3]]
[[0,1],[0,0]]
[[[0]],[[1],[2,3]]]