>>> import numpy as np
>>> A=[[2,-1,3],[4,-2,0],[-3,3,6]]
>>> A
[[2, -1, 3], [4, -2, 0], [-3, 3, 6]]
>>> A=np.array(A)
>>> A
array([[ 2, -1,  3],
       [ 4, -2,  0],
       [-3,  3,  6]])