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: ['C', '3133', '2183', '5793', '9305', 'd', 'g', '6501']
Example Output: 26915

Example Input: ['6051', '5303', '1509', '2797', 'Z', '4777', '721', '8563', 'K', '63', '9115', 'd', '7305', '9743', '7409']
Example Output: 63356

Example Input: ['P', 'p', 'u', '367']
Example Output:
367