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: ['2469', 'c', '6931', 'a', '2167', '9493', '9403', '4123', '4949', 'R', 'V', 'h', '315', 'T', '9411', 'M', '1329', '8217', '6105', 'Y']
Example Output: 64912

Example Input: ['z', 'U', '6817', 's', '3731', 'M', 'I', '1095', 'l', '5993', '5207', 'e', 'L', '5361', 'v', 'g', '1963', '4829', '9541', '8261']
Example Output: 52798

Example Input: ['4979', '4859']
Example Output:
9838