Task - Filter lists

You are given a list of strings. Some of those strings may contain integers, for example Digital Car33r Institute. Implement a method digit_filter that takes a list of strings as an argument and only returns those strings that don't contain a number.

Input:

l33t = ['Digital Car33r Institute', 'DCI', 'Digital', 'Career', 'Inst1tut3']

Output:

> digit_filter(l33t)

['DCI', 'Digital', 'Career']