import numpy as np
arr = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9], [10, 11, 12], [13, 14, 15], [16, 17, 18]])
newarr = np.array_split(arr, 3)
print(newarr)
[array([[1, 2, 3], [4, 5, 6]]), array([[ 7, 8, 9], [10, 11, 12]]), array([[13, 14, 15], [16, 17, 18]])]