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Python Python Collections (Retired) Dictionaries Membership

Nick Smith
Nick Smith
6,688 Points
Posted by Nick Smith
Nick Smith
6,688 Points

This works in workspace but not on submission page.

def members(dic, keys): count = 0 for i in list: if i in dic: count+=1 return count

dict = {'apples':1, 'bananas': 2, 'coconuts':3, 'tacos':1} list= ['apples', 'coconuts', 'strawberries', 'oranges', 'tacos']

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

2 Answers

jacinator
jacinator
11,936 Points
jacinator
jacinator
11,936 Points 
def members(dic, keys):
    count = 0
    # for i in list:  # list is not defined, so you can't loop through it. I'm surprised this worked in workspaces.
    for i in keys:
        if i in dic:
            count+=1 
    return count
jacinator
jacinator
11,936 Points 
# Because I like list comprehension, this works too.
def members(dictionary, keys):
    return len([key for key in keys if key in dictionary])
Hara Gopal K
PLUS
Hara Gopal K
Courses Plus Student 10,027 Points
Hara Gopal K
Hara Gopal K
Courses Plus Student 10,027 Points

i was wondering why this shouldn't work ?

def members (my_dict, my_list): return len (my_list) return my_dict.keys ()

Nick Smith
Nick Smith
6,688 Points
Nick Smith
Nick Smith
6,688 Points

You need a for loop to count key/value. Also you have two return statements. Once it reaches the first return statement, the code stops running and returns that value. So it will never get to your my_dict.keys ()