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: ['3145', 'C', '7725', 'k', 'z']
Example Output: 10870

Example Input: ['7771', 'g']
Example Output: 7771

Example Input: ['q', 'y', 'a', 'f', '9975', 'o', '4711', 'q', 'd', 'g', 'V', '8021', 'Q']
Example Output:
22707