oop_game3,py.py

# One option would be to use a signal system

# Firstly, we have a reusable class that lets you define a signal

class Signal(object):
    def __init__(self):
         self._handlers = []

    def connect(self, handler):
         self._handlers.append(handler)

    def fire(self, *args):
         for handler in self._handlers:
             handler(*args)
# Your item class uses this signal to create a destroyed signal that other classes can listen for.

 class Item(object):
    def __init__(self):
        self.destroyed = Signal()

    def destroy(self):
        self.destroyed.fire(self)
# And inventory listens to the signals from the items and updates its internal state accordingly

 class Inventory(object):
     def __init__(self):
         self._items = []

     def add(self, item):
         item.destroyed.connect(self.on_destroyed)
         self._items.add(item)

     def on_destroyed(self, item):
         self._items.remove(item)