Game doesn't work - see error

[Robin-Andrews]

Player hand is=
Traceback (most recent call last):
File "blackjack.py", line 251, in
deal_cards()
File "blackjack.py", line 138, in deal_cards
game_step()
File "blackjack.py", line 197, in game_step
player_hand.draw(hidden=False)
File "blackjack.py", line 68, in draw
self.cards[x].draw()
File "blackjack.py", line 30, in draw
print(str(self.rank + self.suit))
TypeError: must be str, not Deck