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.

['8871', '1297', 'W', 'f', 'Y', '8731', '113', '6707', '379', '9631', 'X', 'C', 'q']
35729

['z', 'T', 'Y', 's', 'j', '585', '7833', '2601', '8057', 'S', '7037', '5799', '4477', '5377', '6301', 'P', 'm', '9431', 'f']
57498

['2915', '4443', 'Z', '3409', '1417', 'H', 'T', 'u', '3373', 'U', '115', 'R']

15672