Remove all the elements that occur in one list from another

Question

Let\'s say I have two lists, l1 and l2. I want to perform l1 - l2, which returns all elements of l1 not in l2

Answer 1

Python has a language feature called List Comprehensions that is perfectly suited to making this sort of thing extremely easy. The following statement does exactly what you want and stores the result in l3:

l3 = [x for x in l1 if x not in l2]

l3 will contain [1, 6].