Merge pull request #3628 from feyrkh/main

Fix incorrect example code in equipment tutorial

docs/source/Howtos/Beginner-Tutorial/Part3/Beginner-Tutorial-Equipment.md

@@ -402,18 +402,19 @@ class EquipmentHandler:
             to_backpack = [obj]
         else:
             # for others (body, head), just replace whatever's there
-            replaced = [obj]
+            to_backpack = [slots[use_slot]]
             slots[use_slot] = obj
        
         for to_backpack_obj in to_backpack:
             # put stuff in backpack
-            slots[use_slot].append(to_backpack_obj)
+            if to_backpack_obj:
+                slots[WieldLocation.BACKPACK].append(to_backpack_obj)
        
         # store new state
         self._save() 
 ``` 
 
-Here we remember that every `EvAdventureObject` has an `inventory_use_slot` property that tells us where it goes. So we just need to move the object to that slot, replacing whatever is in that place from before. Anything we replace goes back to the backpack. 
+Here we remember that every `EvAdventureObject` has an `inventory_use_slot` property that tells us where it goes. So we just need to move the object to that slot, replacing whatever is in that place from before. Anything we replace goes back to the backpack, as long as it's actually an item and not `None`, in the case where we are moving an item into an empty slot.
 
 ## Get everything 
 
@@ -612,4 +613,4 @@ _Handlers_ are useful for grouping functionality together. Now that we spent our
 
 We also learned to use _hooks_ to tie _Knave_'s custom equipment handling into Evennia.
 
-With `Characters`, `Objects` and now `Equipment` in place, we should be able to move on to character generation - where players get to make their own character!
+With `Characters`, `Objects` and now `Equipment` in place, we should be able to move on to character generation - where players get to make their own character!