def test_remove(self):
lk = LinkedList()
for i in range(0, 10):
lk.add_first(i)
lk.remove_first()
assert lk.get_first() == 8
lk.remove_last()
assert lk.get_last() == 1
def test_set_elememt(self):
lk = LinkedList()
for i in range(0, 10):
lk.add_first(i)
assert lk.get_first() == 9
lk.set(9, 99)
assert lk.get_last() == 99
lk.set(5, 788)
assert lk.contains(788) is True
