is there an opposite of extend function?

I was wondering if there is a function that behaves like extend, only the other way around.
for example if i have a One list that contains numbers from 1 to 10 And letters from A to Z,and another list that contains only Letters from A to Z.
is there a way to substract the second list from first one, so that the first one would contain only numbers.

or do i have to remove all the letters one by one.

I think you’d have to do it one by one, or at least you could do

for item in second:

thanks for replying

thats what im currently using.
it does the job.
i was just looking some more comfortable way to do it.

Try this:

list_a = ["A","B","C","D",1,2,3,4]
list_b = ["A","B","C","D"]
list_diff = list(set(list_a).difference(set(list_b)))
print list_diff