Get the values of the box pertaining to the specified row and column of the Sudoku

def box(self, row, col):
        """Get the values of the box pertaining to the specified row and column of the Sudoku"""
        box = []
        box_i = (row // self.order) * self.order
        box_j = (col // self.order) * self.order
        for i in utils.range_(box_i, box_i + self.order):
            for j in utils.range_(box_j, box_j + self.order):
                box.append(self[i][j])
        return box