How to multiply a matrix with herself, until the zero matrix results

[peanutbutterandjelly]

Hi there!

I'm not quite sure how to code the following problem:
I have to multiply a given matrix A with herself that often, until the zero matrix results.

The matrix A is the following (using numpy as np):
A = np.array([[2,2,2,2,-4], [7,1,1,1,-5], [1,7,1,1,-5], [1,1,7,1,-5], [1,1,1,7,-5]])

Could it be the while loop? But I haven't succeeded yet.