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Python Python Collections (Retired) Dictionaries Membership

Posted by Andrew St. Lazare
Andrew St. Lazare
12,594 Points

function named members Return a count of how many of items in the list are also keys in the dictionary.

***python it is giving me an error saying "expected 2 , got 4".

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(my_dict, my_list):
  count = 0
  for key in my_list:
    count += 1
  return count

1 Answer

Bailey Smith
Bailey Smith
1,645 Points
Bailey Smith
Bailey Smith
1,645 Points

You counted the number of items in my_list. You need to compare these to the keys in the dictionary. in your for loop try

if key in my_dict:
  count += 1
Andrew St. Lazare
Andrew St. Lazare
12,594 Points

It didn't work either but, thank you for trying!