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: ['5899', '229', 'm', '3347', 'k', 'q', 'g', '2755', '8727', '2035', '823', '6835', '9271', 'Q']
Example Output: 39921

Example Input: ['1057', '3937']
Example Output: 4994

Example Input: ['8319', '4993', 'i', 'e', '7783', 'b', 'O', '6431', '3345', 'B', 'p']
Example Output:
30871