def matrix_times(A,B):
    C = []
    for m in range(len(A)):
        row = []
        for n in range(len(B[0])):
            entry = 0
            for k in range(len(A)):
                entry += A[m][k] * B[k][n]
           # print(entry)
            row += [entry]
        #print(row)
        C += [row]
    return C

matrix_0 = [[1, 0, 0],
            [0, 4, 0],
            [0, 0, 1]]

matrix_1 = [[1, 2, 3],
            [0, 1, 0],
            [0, 0, 1]]



Q = matrix_times(matrix_0,matrix_1)

print(Q)