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.

['I', 'J', 'K', 'D', '5961']
5961

['O', '9829', '5265', 'U', 'z', '2843', '1483', '9293', '1327', '2015']
32055

['7667', 'f']

7667