Attribute Error Blackjack Python

Question

I have to modify this program from my text book to use bets but I cant even get the original program to run. This is the program as it appears in the book except each class are on different pages. I'm not sure if I need to even type out all these classes because my professor said take the blackjack program and modify it to accept bets but it imports deck and card so I'm not sure. I typed them out just in case because I figured it wouldn't do much harm maybe I am wrong.

class Card(object):

  RANKS=(1,2,3,4,5,6,7,8,9,10,11,12,13)
  SUITS=('Spades','Diamonds','Hearts','Clubs')

  def _init_(self,rank,suit):
    self.rank=rank
    self.suit=suit

  def _str_(self):
    if self.rank==1:
        rank='Ace'
    elif self.rank==11:
        rank='Jack'
    elif self.rank==12:
        rank='Queen'
    elif self.rank==13:
        rank='King'
    else:
        rank=self.rank
    return str(rank)+ ' of ' + self.suit

import random

class Deck(Card,object):

  def _init_(self):
    self._cards=[]
    for suit in Card.SUITS:
        for rank in Card.RANKS:
            c=Card(rank,suit)
            self._cards.append(c)

  def shuffle(self):
    random.shuffle(self._cards)

  def deal(self):
    if len(self)==0:
        return None
    else:
        return self._cards.pop(0)

  def _len_(self):
    return len(self._cards)

  def _str_(self):
    result=''
    for c in self._cards:
        result= result+str(c)+'\n'
    return result

class Player(Deck,object):

  def _init_(self, cards):
    self._cards= cards

  def _str_(self):
    result=",".join(map(str,self._cards))
    results += "\n " + str(self.getPoints()) + " points"
    return result

  def hit(self,card):
    self._cards.append(card)

  def getPoints(self):
    count=0
    for card in self._cards:
        if card.rank>9:
            count+=10
        elif card.rank==1:
            count+=11
        else:
            count+=card.rank
    for card in self._cards:
        if count <=21:
            break
        elif card.rank==1:
            count -= 10
    return count

  def hasBlackjack(self):
    return len(self._cards)==2 and self.getpoints()==21

class Dealer(Player,object):

  def _init_(self,cards):
    Player._init_(self,cards)
    self._showOneCard= True

  def _str_(self):
    if self._showOneCard:
        return str(self._cards[0])
    else:
        return Player._str_(self)

  def hit(self,deck):
    self._showOneCard= False
    while self.getPoints() <17:
        self.Cards.append(deck.deal())

class Blackjack(Player, object):

  def _init_(self):
    self._deck = Deck()
    self._deck.shuffle()

    self._player = Player([self._deck.deal(),
                           self._deck.deal()])
    self._dealer = Dealer([self._deck.deal(),
                           self._deck.deal()])

  def play(self):
    print ("Player:\n", self._player)
    print ("Dealer:\n", self._dealer)
    while True:
        choice = input("Do you want to hit? [y/n]: ")
        if choice in ("Y","y"):
            self._player.hit(self._deck.deal())
            points = self._player.getPoints()
            print ("Player:\n", self._player)
            if points >= 21:
                break
        else:
            break
    playerPoints = self._player.getPoints()
    if playerPoints> 21:
        print ("You bust and lose")
    else:
        self._dealer.hit(self._deck)
        print ("Dealer:\n", self._dealer)
        dealerPoints=self._dealer.getpoints()
        if dealerPoints >21:
            print ("Dealer busts you win")
        elif dealerPoints>playerPoints:
            print ("Dealer wins")
        elif dealerPoints<playerPoints and playerPoints <= 21:
            print ("You win")
        elif dealerPoints == playerPoints:
            if self._player.hasBlackjack() and not self._dealer.hasBlackjack():
                print ("You win")
        elif not self._player.hasBlackjack() and self._dealer.hasBlackjack():
            print ("Dealer wins")
        else:
            print ("There is a tie")

Blackjack().play()

I get

Traceback (most recent call last):
File "C:\Users\Schuler\bj.py", line 151, in <module>
Blackjack().play()
File "C:\Users\Schuler\bj.py", line 117, in play
print ("Player:\n", self._player)
AttributeError: 'Blackjack' object has no attribute '_player'

I copied everything straight from the book and I can't figure out what is wrong.

_____Edit_____

So It was pointed out I forgot double underscores so I fixed that. Then I ran if like 10 more times and found small spelling mistakes it runs now.

Answer 1

It looks like you left out the double underscores on some of your method definitions. It's __init__, not _init_. Same goes for __str__, __len__, and other special class methods.

These special method names have to be written exactly otherwise they won't work. For instance, if you have a method named __init__ then the code in that method will get run automatically when you instantiate an object of that type. Because you typed it wrong the method never ran and your code gave the error.

A simple illustration of how __init__ works:

class Player(object):
    def __init__(self):
        print 'new player object'

Player() # __init__() called automatically and prints 'new player object'