Python Dictonary Class

Question

I am trying to get my class working but I can only seem to add 2 items and I can't add the duplicate item.

I have also tried using for loops but I can't seem to get that to work either.

List of words to add:

words = Bag()
words.add('once')
words.add('twice')
words.add('twice')

My code:

class Bag:
 def __init__(self):
 """Create a new empty bag."""
 self.bag = dict()
 def add(self, item):
 """Add one copy of item to the bag. Multiple copies are allowed."""
 if not item in self.bag:
 self.bag[item] = 1
 else:
 self.bag[item] += 1
 print(self.bag)

• sanyassh: But... your code is working.
• Thierry Lathuille: Your code works perfectly for me. Do you get an error? What is your expected vs actual output?
• M Y: for x in self.bag.values(): print(x)
• Cypher: thank you for your replies, my code works to a point i cant get my code to add 'twice' twice into my dictionary only shows 2 entries and not 3 item

Answer 1

You want results to look like {'once': 1, 'twice': 2, 'twice': 3}.

This is not possible, you can't have same key multiple times in a dict. But you can get structure like [{'once': 1}, {'twice': 2}, {'twice': 3}] with this code:

from collections import defaultdict
class Bag:
 def __init__(self):
 """Create a new empty bag."""
 self.index = 0
 self.bag = []
 def add(self, item):
 """Add one copy of item to the bag. Multiple copies are allowed."""
 self.index += 1
 self.bag.append({item: self.index})

• Cypher: thank you for your replies, my code works to a point i cant get my code to add 'twice' twice into my dictionary only shows 2 entries and not 3 items
• jozo: How should correct result looks like? Isn't {'once': 1, 'twice': 2} correct?
• Cypher: the correct result should look like this {'once': 1, 'twice': 2, 'twice': 3}
• jozo: I edited my answer. You can't get what you want but you can have something similar.
• Cypher: Genius! thank you! I understand where I went wrong now!