pygame scrolling camera issue

Question

I have x and y scrolling with the following code working fine, but it always starts from top left of map, and I wish it to start wherever the player object is positioned (player obj is called at particular tile position in map).

#update scroll
    if self.char == 'hero':
        if (self.rect.right > (screen_width//2 + 30) and self.direction_x == 1 and bg_scroll[0] < level_length - screen_width)\
         or (self.rect.left < (screen_width//2 - 30) and self.direction_x == -1 and bg_scroll[0] > abs(dx)):
            self.rect.x -= dx
            scroll[0] = -int(dx)
        if (self.rect.bottom > (screen_height//2 +40) and self.direction_y ==1 and bg_scroll[1] < level_height - screen_height) \
        or (self.rect.top < (screen_height//2 - 40) and self.direction_y == -1 and bg_scroll[1] > abs(dy)):
            self.rect.y -= dy
            scroll[1] = -int(dy)

So I have tried for days to integrate a camera class and make my player obj the target but it has not worked and I have now created a variable that shows the full maps x/y position trying to use this minus player position to set the scroll speed but it does not work.

I feel to get the desired result I will to recode this with a proper camera class based around the object but I am struggling, Please help!