What is the correct way to concatenate numpy arrays?

Question

Python

There is some code like this

from skimage import io
import numpy as np
a = io.imread("ссылка1")
b = io.imread("ссылка2")

And if I use np.append(a, b)it, I will end up with a one-dimensional array with all the values ​​from the array a and b, and I need to create a new array of the type [array a, array b], using exactly numpy