Question

I have a list and I want to assign a random element from that list to a new variable five times in order to generate a hand of cards. I’ve searched, and I can’t seem to understand why my random.choice is causing errors.

import random

cards = { '2' '3' '4' '5' '6' '7' '8' '9' 'J' 'Q' 'K' 'A' }

for newCard in range(5):
        newDraw = random.choice(cards)
        playerdeck.append(newDraw)
        if newDraw in playerdeck:
                playermatches = playermatches + 1
        newDraw = oldDraw

When I try to run it I get this error:

Traceback (most recent call last):
  File "C:\Users\Nathaniel\Desktop\Fcard.py", line 6, in <module>
    newDraw = random.choice(cards)
  File "C:\Python32\lib\random.py", line 253, in choice
    return seq[i]
TypeError: 'set' object does not support indexing

Answer 1

You used { and } rather than [ and ] to define cards. Therefore, it is a set. sets are not ordered, and therefore it makes no sense to try to index into it. random.choice needs to index into a collection to pull an item out of it. Anyway, a quick fix is to replace this:

random.choice(cards)

With this:

random.choice(list(cards))

Edit: Also add commas between the elements in the set.