Retrieve only non-duplicate elements from a list

Question

What is the best option to retrieve only non-duplicate elements from a Python list? Say I have the following list:

lst = [1, 2, 3, 2, 3, 4]

I w

Answer 1

Use collections.Counter to get counts of items. Combine with a list comprehension to keep only those that have a count of one.

>>> from collections import Counter
>>> lst = [1, 2, 3, 2, 3, 4]
>>> [item for item, count in Counter(lst).items() if count == 1]
[1, 4]