如何在cntk中输出形状？

import cntk as C

# 创建一个输入张量
input_tensor = C.input_variable(shape=(3, 4, 5))

# 输出张量的形状
shape = C.shape(input_tensor)

print(shape.eval({input_tensor: [[[1, 2, 3, 4, 5],
                                   [6, 7, 8, 9, 10],
                                   [11, 12, 13, 14, 15],
                                   [16, 17, 18, 19, 20]],
                                  [[21, 22, 23, 24, 25],
                                   [26, 27, 28, 29, 30],
                                   [31, 32, 33, 34, 35],
                                   [36, 37, 38, 39, 40]],
                                  [[41, 42, 43, 44, 45],
                                   [46, 47, 48, 49, 50],
                                   [51, 52, 53, 54, 55],
                                   [56, 57, 58, 59, 60]]]}))

(3, 4, 5)