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: ['507', 'P', '9697', 'u', '5057']
Example Output: 15261

Example Input: ['4161', 'E']
Example Output: 4161

Example Input: ['A', '2449', '1007', '7623', 'D', 'p', 'M', 'I', 'h', 'R', 'r', '2951', '7633', 'Z', '6195', 'j']
Example Output:
27858