python remove everything except numbers from string code example

Example 1: python remove all except numbers

>>> import re
>>> re.sub('\D', '', 'aas30dsa20')
'3020'

Example 2: python remove everything except numbers from string

def AdvancedIn(in_string):
    res = ''.join(i for i in input(in_string) if i.isdigit())
    return res