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: ['8683', 'p', '47', '8983', 'g', 'u']
Example Output: 17713

Example Input: ['R', 'k', '3355', 'Y', '6635', 'M', '4839', 'T', 'd', '495', 'g', 'E', 'g', 'F', 'S', '5377', 'g']
Example Output: 20701

Example Input: ['h', '6239', '8291', 'b', 'a', 'i', 'l', 'V', '7915', '8341', 'v', '3435', 'H', '111', '9813']
Example Output:
44145