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Python Python Collections (Retired) Dictionaries Membership

Posted by Sumit Bandyopadhyay
Sumit Bandyopadhyay
823 Points

How to check the dictionary membership ?

Syntax for checking the dictionary membership

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(dicts,lkeys):
    count = 0
    for key in dicts:
        ++count
    return count

1 Answer

Kourosh Raeen
Kourosh Raeen
23,733 Points
Kourosh Raeen
Kourosh Raeen
23,733 Points

Hi Sumit - First, I would suggest looping over your list of keys instead of the dictionary. Then for each item in the list you can see if it is a key in the dictionary with an if statement:

if key in dicts:
  # increment count

Also, double check the syntax for incrementing count.