You were pretty close:
import itertools
l = [1,2,3,4,5,6]
ts = 8
def psl(l, ts):
for i in range(len(l)):
for c in itertools.combinations(l, i):
if sum(c) == ts:
print list(c)
psl(l, ts)
solved Print all combinations of list that sum to a number [closed]