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.

Input: Consider Input: ['4949', '2459', 'n', 'f', 'n', 'v', '8421', '1519', '4859', 'c', '9923', '2829', 'K', '4937', 'W', 'R']

Output: 39896

Input: Consider Input: ['Y', 'X', 'd', 'N', '1877', '2865', 'M', '1249', '9385', 'v', 'o', 'P', 'P', '6029']

Output: 21405

Input: Consider Input: ['7335', '813', '6461', '8903', '3709', 'V', 'G', 'I', 'P', 'p', 's', 'v', 'R', '4697', '4263', '9897']
Output: 46078