>>> a = np.array([[[1,2,3],[4,5,6]]])
>>> a
array([[[1, 2, 3],
        [4, 5, 6]]])
>>> a.shape
(1, 2, 3)

>>> new_a
array([[[1, 4]],
       [[2, 5]],
       [[3, 6]]])

>>> a.reshape((3,1,2))
array([[[1, 2]],
       [[3, 4]],
       [[5, 6]]])