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Python Python Basics (2015) Letter Game App Random Item

Posted by Mark Baek
Mark Baek
1,172 Points

Checking work results in: TypeError: unsupported operand type(s) for -: 'list' and 'int'. Running in shell does not.

The purpose of this code is to recreate the random.choice method.

When I check my work, I get the "TypeError: unsupported operand type(s) for -: 'list' and 'int'" message.

When I run this in Python shell, I don't get any error message. However I don't get any output from the shell either when I change "return" to "print".

Any hints? I used brackets instead of parentheses on line 6 as I believe that's what you need to do to get the character located at that index?

item.py 
import random

def random_item(item):
    item_selector = random.randint(0, len(item - 1))

    return(item.index[item_selector])

1 Answer

Carlos Federico Puebla Larregle
Carlos Federico Puebla Larregle
21,074 Points
Carlos Federico Puebla Larregle
Carlos Federico Puebla Larregle
21,074 Points

Just use the "item_selector" variable as the index of your item list, and put your "- 1" out of the parenthesis of the "len" function, like this:

import random

def random_item(item):
    item_selector = random.randint(0, len(item) - 1)

    return item[item_selector]

I hope that helps a little bit.

Mark Baek
Mark Baek
1,172 Points

Thanks, that helps a lot. What this tells me is that I need to focus on learning better syntax, and that it's too early and I need to take a break!