Python - comparing values in the same dictionary

Question

I have a dictionary:

d = {\'Trump\': [\'MAGA\', \'FollowTheMoney\'],
     \'Clinton\': [\'dems\', \'Clinton\'],
     \'Stein\': [\'FollowTheMoney\', \'Atlant         


        

Answer 1

You can use Counter to tally how many times each value appears in d.

d = {'Trump': ['MAGA', 'FollowTheMoney'],
     'Clinton': ['dems', 'Clinton'],
     'Stein': ['FollowTheMoney', 'Atlanta']}

from collections import Counter

c = Counter(x for xs in d.values() for x in xs)

In this example, the value of c is

Counter({'Atlanta': 1,
         'Clinton': 1,
         'FollowTheMoney': 2,
         'MAGA': 1,
         'dems': 1})

Then choose values for which the count is exactly 1.

update_d = {k: [v for v in vs if c[v] == 1] for k, vs in d.items()}

Answer 2

Not as elegant as using Counter, but does remove duplicates without the use of modules:

d = {'Trump': ['MAGA', 'FollowTheMoney'],
    'Clinton': ['dems', 'Clinton'],
    'Stein': ['FollowTheMoney', 'Atlanta']}

dupvals = [item for sublist in d.values() for item in sublist] # get all values from all keys into a list
dups = [] # list to hold duplicates

for i in dupvals:
    if dupvals.count(i) > 1:
        dups.append(i)

dupvals = set(dups) # keep only one item for each duplicated item

new_d = {}

for key,values in d.items():
    for value in values:
        if not value in dupvals:
            new_d.setdefault(key, []).append(value)

print new_d # {'Clinton': ['dems', 'Clinton'], 'Trump': ['MAGA'], 'Stein': ['Atlanta']}