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Python Python Collections (Retired) Dictionaries Membership

What's wrong?? (Python Collections)

"Bummer! list indices must be integers, not str". That's the error. Great moons of Jupiter! What's wrong???

counts.py
# You can check for dictionary membership using the
# "key in dict" syntax from lists.

### Example
# my_dict = {'apples': 1, 'bananas': 2, 'coconuts': 3}
# my_list = ['apples', 'coconuts', 'grapes', 'strawberries']
# members(my_dict, my_list) => 2
def members(dic, li):
  times = 0
  for x in dic:
    if li[x] == x:
      times += 1
  return int(times)

2 Answers

Kenneth Love
STAFF
Kenneth Love
Treehouse Guest Teacher
if li[x] == x

At this point, li is the list and x is a key from the dictionary. You're asking for the index from a list using a string key from a dict. You can't use strings for list indexes.

thanks!

Hi there,

Have a look through this post and see if that helps you out.

Steve.