Rotating-matrix-90-degrees with python

Introduce method to rotate python matrix by 90-degrees without libraries. If you know the principles without additional libraries or complex code, you can easily solve them with simple python code. I hope you can acquire the following code by savoring it deeply.✍️

def rotate_matrix_90_degrees(a):
    # length of row
    n = len(a)
    # length of column
    m = len(a[0])
		
    # array for storing result
    result = [[0] * n for _ in range(m)]
		
    # rotating element with rule
    # if you couldn't under standing, drawing it on paper!
    for i in range(n):
        for j in range(m):
            result[j][n-i-1] = a[i][j]
		
    return result

This post is part of Python-Team-Notes for coding test posting that I posted. If you have any questions or mistakes regarding the code, please point it out!