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.

['s', '425', '6135']
6560

['s', '3607', 'p', 'P', '9285', 'J', 'l', '9863', '9823', '2817', 'g', '9751', '599', '2605', 'k', 'Y', 'O', 'U', '9649']
57999

['777', '6811', 'D', '8891', '2605', '3005', 'I', 't', '9349', 'X', 'k', '5083', '6219']

42740