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: ['8743', 'Y', 'O', '8265', '1029', '5689', 'F', 'j', 'Z', 'i', 'S', '1285', '737']
Example Output: 25748

Example Input: ['F', 'z', '1159', '345']
Example Output: 1504

Example Input: ['5253', 's', '197']
Example Output:
5450