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: ['Q', '2271', '1803', '2363']
Example Output: 6437

Example Input: ['8763', 'k', '3653', 'v', 'd', 'D', 'm', '1037', 'c', 'F', '2349', '7843', '3259', 'v', '5555', '7565', '8137', 't']
Example Output: 48161

Example Input: ['4283', 'o', '2067', 'K', 'm', '961', 'y', '2413', '7945', '7685', 'o', '609', '5893', 'x', '9399']
Example Output:
41255