def __add__(self, other):
    result = []
    matrix_size = self.size()
 
    if self.size() == other.size():
        for i in range(matrix_size[0]):
            row = []
            for j in range(matrix_size[1]):
                row.append(self.matrix[i][j] + other.matrix[i][j])
            result.append(row)
    return Matrix(result)