执行下列代码，输出结果是？（ ）
import numpy as np x=[(0,1,2),(3,4,5),(6,7,8)] a=np.asarray(x) print (a)
[(0 1 2)
(3 4 5)
(6 7 8)]
[(0 1 2),
(3 4 5),
[[0 1 2]
[3 4 5]
[6 7 8]]
[[0 1 2],
[3 4 5],
