//Forward declare any custom functions
    void my_function();
    void setup()
    {
        set_interval(2000, my_function);
    }
    void loop()
    {
        think();
        act();
    }
    void think()
    {
        block_value = weighted_average(neighbor_data);
    }
    void act()
    {
        set_drive(255);
        if( block_value > 127)
        {
            //Stop toggling directions
            clear_interval();
        }
    }
    void my_function()
    {
        //This function will be called every two seconds.
        toggle_directions();
    }