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sidni ahmed
3,329 PointsWrite a function named members
can someone please help me with this? i'm just confused what to do in the function part
# 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 = {'apples': 1, 'bananas': 2, 'cocunuts': 3}
my_list = ['apples', 'cocunuts', 'strawberries', 'grapes']
def members(my_dict, my_list):
3 Answers
Seth Reece
32,867 PointsHi Sidni,
What you want here is to loop through the keys in a dictionary and check if they are also in the list. e.g.
def members(my_dict, my_list):
x = 0
for key in my_dict:
if key in my_list:
x += 1
return x
sidni ahmed
3,329 Pointswhat i don't get is why x = 0. the we do x += 1. what is going on here? its puzzling
Seth Reece
32,867 PointsEvery time a key in my_dict is found in my_list we increment x to return a count of matching items.
sidni ahmed
3,329 Pointsi'm sorry to bother you, but one quick question. it's just that how is it that if i add keys in the dictionary that are in the list. How does the function know which keys are the same? I understand we increment x to return matching items, but how does it even know the items are even matching? i think i maybe confusing myself her
Seth Reece
32,867 PointsIn this loop we go through all they keys in my-dict one at a time. That key is stored in the variable key. Then check if it's in my_list. If it is increase x by one.