In this task, you are given an input list A. You need to find all the elements of the list that are numbers and calculate their sum.

['Z', 'w', 'M', '2233', '5275', '5277', 's', '971', '7085', '6259', 'V', 'E', '4923', '7365', 'c', 'd', 'c', 'U', 'P']
39388

['t', '7469', 'Y', 'N', '8137']
15606

['2879', '2173', 'k', 't', 'y', 'l', '4393', '6659', '7499', 'a', '969']

24572