Unlocks this item from its attachment slot of its parent. 
  856    {
  857        EntityAI parent = GetHierarchyParent();
 
  858        
  859        if (parent)
  860        {
  861            InventoryLocation inventory_location_to_unlock = new InventoryLocation;
  862            GetInventory().GetCurrentInventoryLocation(inventory_location_to_unlock);
  863            parent.GetInventory().SetSlotLock(inventory_location_to_unlock.
GetSlot(), 
false);
 
  864        }
  865    }
proto native int GetSlot()
returns slot id if current type is Attachment