Question

i used this code, but this codes only removes the duplicates on the list and returns the list without duplicates for example if i had a = [1,1,2,3,3,4,6]
when i used the bottom codes it giving outputting this a = [1,2,3,4,6]. but i want to only ouput the integer that appears only once ex i want this [2,4,6] can anyone help pleaseee stayed up all night trying to figure this out

def unique(a):
    order = set()
    order_add = order.add
    return [x for x in a if x not in order and not order_add(x)]

Answer 1

To preserve order while removing items with duplicates:

>>> from collections import Counter
>>> x = [1, 2, 3, 2, 1, 8]
>>> counts = Counter(x)
>>> [item for item in x if counts[item] == 1]
[3, 8]