def compute_sized_powerlevel(grid, x, y, size=3):
    """
    Compute combined powerlevel for sizexsize grid with topleft element (x,y).
    """
    total_power_level = 0
    for i in range(size):
        for j in range(size):
            total_power_level += grid[(x+i, y+j)]
    return total_power_level