Заполнить квадратную матрицу

width = int(input('Ширина:'))
height = int(input('Высота:'))
square = []
for y in range(height):
    square.append([])   
    for x in range(width):
        square[y].append(None)

n = 10
lst = [[0 for i in range(n)] for j in range(n)]
for i in range(n):
    lst[i][i] = n
    n -= 1
 
for line in lst:
    print(line)

n=range(int(input()))
a=[]
for i in n:
    a.append([0 if j!=i else len(n)-j for j in n])
print(*a,sep='\n')

n = 10
a = [[[n-j, 0][i != j] for i in range(n)] for j in range(n)]
print(*a, sep='\n')

class DiagonalMatrix(object):
    def __init__(self, n):
        self.n = n
 
    def __getitem__(self, item):
        i, j = item
        if i != j:
            return 0
        else:
            return self.n - i
 
n = 3
 
m = DiagonalMatrix(n)
for i in range(n):
    for j in range(n):
        print (m[i, j], end=' ')
    print('\n')