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: ['m', 'g', '7251', '5873', '59', '7345']
Example Output: 20528

Example Input: ['v', '4119', 'I', '475', 'd', 'L', '909', 'F', 'V', '775', 'k', 'A', '9411', '8383', 'W', '1521', 'z', 'j', '7057', 'I']
Example Output: 32650

Example Input: ['6207', '4929', 'A', 'e', '6587', 't', '6501', '4237']
Example Output:
28461