code: def get_deck(self):
          
          trace = self.get_trace()
  
          # Find decks in trace, prepend with [None] in case nothing was found
          res = [None] + [item for item in trace if isinstance(item, Deck)]
  
          # Pop last (and hopefully only Deck) or None if there is no deck
          return res.pop()
docs: Returns parent :Deck: of a :Placeable: