How to insert data in a numpy array, preserving its shape?

I have a collection of several data of fixed shape, and I need to store these values in an array, only creating a new dimension, so I can preserve its initial shape. Here is a small example,

arr = np.array([0,1,2])
values = np.array([[3,4,5], [6,7,8], [9,10,11]])

n = 3

for i in range(n):
    arr = np.append(arr, values[n])

I need the code to output something simmilar to

>> array([[0,1,2],[3,4,5],[6,7,8],[9,10,11]])

But i can only find

>> array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11])
Is there a function that can handle this problem?

>Solution :

This is an easy one. Reshape your arr into a 2d array and add an axis argument to np.append.

import numpy as np
arr = np.array([0,1,2])
values = np.array([[3,4,5], [6,7,8], [9,10,11]])

out = np.append(arr.reshape(1,-1),values,axis=0)
print(out)

Yields:

[[ 0  1  2]
 [ 3  4  5]
 [ 6  7  8]
 [ 9 10 11]]