Get a unique list of items that occur more than once in a list

Question

I have a list of items:

mylist = [\'A\',\'A\',\'B\',\'C\',\'D\',\'E\',\'D\']

I want to return a unique list of items that appear more than

Answer 1

Try some thing like this:

a = ['A','A','B','C','D','E','D']

import collections
print [x for x, y in collections.Counter(a).items() if y > 1]
 ['A', 'D']

Reference: How to find duplicate elements in array using for loop in Python?

OR

def list_has_duplicate_items( mylist ):
    return len(mylist) > len(set(mylist))
def get_duplicate_items( mylist ):
    return [item for item in set(mylist) if mylist.count(item) > 1]
mylist = [ 'oranges' , 'apples' , 'oranges' , 'grapes' ]
print 'List: ' , mylist
print 'Does list have duplicate item(s)? ' , list_has_duplicate_items( mylist )
print 'Redundant item(s) in list: ' , get_duplicate_items( mylist )

Reference https://www.daniweb.com/software-development/python/threads/286996/get-redundant-items-in-list