import re


def numbered_file_names_sort(x):
    """
    Key function for 'sorted'.\n
    Sorts a list of Strings according to al numbers contained in the String.\n
    All numbers will be simply concatenated.

    :param x: input of the key function
    :return: all numbers contained in x concatenated and converted to int
    """
    nums = [s for s in re.findall(r'\d+', x)]
    num = int(''.join(nums))
    return num