Create a function that takes a list of strings and integers, and filters out the list so that it returns a list of integers only.
filter_list([1, 2, 3, "a", "b", 4]) ➞ [1, 2, 3, 4]
filter_list(["A", 0, "Innokodakademija", 1729, "Python", "1729"]) ➞ [0, 1729]
filter_list(["Nothing", "here"]) ➞ []
Don't overthink this one.