in set vs in list

gistfile1.txt

brendand@brendand-T450:~$ cat algo.py 
L = list(range(1000000))
LS = set(L)

def findit():
    if 500000 in L:
        pass
def findset():
    if 500000 in LS:
        pass

import timeit

print(timeit.timeit('findit()', 'from __main__ import findit', number=1000))
print(timeit.timeit('findset()', 'from __main__ import findset', number=1000))
brendand@brendand-T450:~$ python algo.py 
4.09275507927
0.000100135803223