python 构造三维全零数组的方法

temp1 = [[] for i in range(10)]
temp2 = [temp1 for i in range(20)]
temp3 = [temp2 for i in range(30)]
for i in range(30):
 for j in range(20):
  for k in range(10):
   temp3[i][j][k] = 0

matrix3d=[]
for i in range(30):
 matrix3d.append([])
 for j in range(20):
  matrix3d[i].append([])
  for k in range(10):
   matrix3d[i][j].append(0)