Removing an element from a list based on a predicate

Question

I want to remove an element from list, such that the element contains \'X\' or \'N\'. I have to apply for a large genome. Here is an example:

Answer 1

For basis purpose

>>> [x for x in ['AAT','XAC','ANT','TTA'] if "X" not in x and "N" not in x]
['AAT', 'TTA']

But if you have huge amount of data, I suggest you to use dict or set

And If you have many characters other than X and N, you may do like this

>>> [x for x in ['AAT','XAC','ANT','TTA'] if not any(ch for ch in list(x) if ch in ["X","N","Y","Z","K","J"])]
['AAT', 'TTA']

NOTE: list(x) can be just x, and ["X","N","Y","Z","K","J"] can be just "XNYZKJ", and refer gnibbler answer, He did the best one.