a = range(10)
a = filter(lambda n: n%2 != 0, a)
it will give you
[1, 3, 5, 7, 9]
As you can see, no more six (and the same will happen with any multiple of six)
then, if you delete multiples of three
a = filter(lambda n: n%3 != 0, a)
a will be [1, 2, 4, 5, 7, 8]