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.

['a', 'm', '3205', '1869', '1117', 'K', '5785']
11976

['O', '6337', 'j', '6009', 'z']
12346

['9615', 'P', 'P', '7663', '5203', 'h', '4997', 't', 'r', 'P', '5807', '1217', 'N', '3513', 'u']

38015