Please write a function that sums a list, but ignores any duplicate items in the list.

For instance, for the list [3, 4, 3, 6] , the function should return 10.

Source: codewars | Difficulty: EASY
Tags: Fundamentals

Starter code: def sum_no_duplicates(l):
	

Solutions:
from collections import Counter

def sum_no_duplicates(nums):
	return sum((k for (k, v) in list(Counter(nums).items()) if v == 1))


def sum_no_duplicates(l):
	return sum((n for n in set(l) if l.count(n) == 1))


def sum_no_duplicates(l):
	return sum([e for e in l if l.count(e) == 1])


from collections import Counter

def sum_no_duplicates(xs):
	return sum((x for (x, c) in Counter(xs).items() if c == 1))


sum_no_duplicates = lambda L: sum([n for n in L if L.count(n) == 1])


def sum_no_duplicates(arr):
	return sum((i for i in set(arr) if arr.count(i) == 1))


from collections import Counter

def sum_no_duplicates(l):
	c = Counter(l)
	return sum((k for (k, v) in c.items() if v == 1))


def sum_no_duplicates(l):
	return sum((x for x in set(l) if l.count(x) < 2))