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.

['1671', 'H', '9271']
10942

['7361', '6913', '3605', '2081', '7619']
27579

['5055', 'U', 't', 'N', '1931', 'G', '3835', '1631']

12452