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: ['s', 'g', 'Z', '8919', 'R']
Example Output: 8919

Example Input: ['j', 'A', 'L', 'i', 'I', '3827', '8245', 'H', 'J', '8117', 'w', '4659', 'Y', 'x', 'K']
Example Output: 24848

Example Input: ['6245', '9157', 'u', '5639', '2493', 'Q', 'N', 'Z', '3109', 'A', '1093', '8311', '3753', '5717', 's']
Example Output:
45517