anchor.diff:  	to_chat(user, "<span class='notice'>You take \the [tank] from \the [src].</span>")
   	add_fingerprint(user)
   	user.put_in_hands(tank)
  +	after_remove_tank()
  +
  +/obj/structure/tank_holder/proc/put_tank(obj/item/tank)
  +	if(!user.transferItemToLoc(W, src))
  +		return
  +	tank = tank
  +	icon_state = tank.tank_holder_icon_state
  +	density = TRUE
  +
  +/obj/structure/tank_holder/proc/after_remove_tank()
   	tank = null
   	icon_state = "holder"
  +	density = FALSE
   
   /obj/structure/tank_holder/oxygen
   	icon_state = "holder_oxygen"
  
positive.code: /obj/structure/tank_holder/Initialize()
  	. = ..()
  	if(tank)
  		density = TRUE
  		tank = new tank(src)
  
  /obj/structure/tank_holder/Destroy()
  	if(tank)
  
negative.code: 	if(!user.transferItemToLoc(W, src))
  		return
  	to_chat(user, "<span class='notice'>You put \the [W] into \the [src].</span>")
  	put_tank(W)
  
  /obj/structure/tank_holder/screwdriver_act(mob/living/user, obj/item/I)
  	if(..())
  