实例如下所示：
>>>from compiler.ast import flatten
>>>X
matrix([[ 1, 17, 13, 221, 289, 169],
[ 1, 17, 14, 238, 289, 196],
[ 1, 17, 15, 255, 289, 225],
[ 1, 18, 13, 234, 324, 169],
[ 1, 18, 14, 252, 324, 196],
[ 1, 18, 15, 270, 324, 225],
[ 1, 19, 13, 247, 361, 169],
[ 1, 19, 14, 266, 361, 196],
[
