hao-gu

def matmul(matrix_a, matrix_b):
    rows_a = len(matrix_a)
    cols_a = len(matrix_a[0])
    rows_b = len(matrix_b)
    cols_b = len(matrix_b[0])
    result_matrix = [[0 for _ in range(cols_b)] for _ in range(rows_a)]
    for i in range(rows_a):
        for j in range(cols_b): 
            for k in range(cols_a): 
                result_matrix[i][j] += matrix_a[i][k] * matrix_b[k][j]