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.

Example Input: ['B', 's']
Example Output: 0

Example Input: ['3451', '2325', '2511', 'i', '6159', '2291', 'e', 'l', 'P', '1177', 'o', 'T']
Example Output: 17914

Example Input: ['403', 'r', 'e', '5639', '4681', 'd', 'A', 's', '5805', '4995', 'k']
Example Output:
21523