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Python Python Collections (Retired) Dictionaries Membership

Posted by Carina De Jager
Carina De Jager
1,779 Points

Can someone take a look at my code and tell me why it's returning none instead of 2?

I'm not quite sure why I'm getting a return of none.

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
my_dict = {'a': 1, 'b': 2, 'c': 3}
my_keys= ['a', 'b', 'c', 'd']

def members(my_dict, my_keys):
  count = 0
  for item in my_keys:
    if item in my_dict.keys():
      count += 1

2 Answers

Daniel Santos
Daniel Santos
34,969 Points

Hi Carina,

If you do not specify the return keyword in a function, it will return None.

If you want to return the count you should do:

return count

inside of the function.

Hope this help.

-Dan

Hanley Chan
Hanley Chan
27,771 Points
Hanley Chan
Hanley Chan
27,771 Points

Hi,

You are missing your return statement. 

def members(my_dict, my_keys):
  count = 0
  for item in my_keys:
    if item in my_dict.keys():
      count += 1
  return count