Entities is initialized as a list, but code treats it as a set.

Line 92 in 6e763f1

dungeon = GameMap(map_width, map_height, entities=[player])

Python 3.10 will break with other parts of the code such as.

for entity in self.game_map.entities - {self.player}:
TypeError: unsupported operand type(s) for -: 'list' and 'set'

It seems to be a simple fix - just declare it as {player}. I didn't make a pull request because I don't know in which part this "mistake" began, or if there's something else I'm missing.

GameMap's initializer always converts that input into a set, this part is missing from your code:

tcod_tutorial_v2/game_map.py

Lines 14 to 17 in 6e763f1

    
           class GameMap: 
        
               def __init__(self, width: int, height: int, entities: Iterable[Entity] = ()): 
        
                   self.width, self.height = width, height 
        
                   self.entities = set(entities)

Your change would be a little more efficient though. Some classes would probably be better written with attrs.

Thank you, I missed that default when following your guide.

I believe it's not worth a change given that.

	class GameMap:
	def __init__(self, width: int, height: int, entities: Iterable[Entity] = ()):
	self.width, self.height = width, height
	self.entities = set(entities)