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

Example Input: ['c', '7415', '6253', '4477', 't', '9449', '7733', '2325', 'Z', '5413', 'q', 'm', 'R', '8619', '7289', '857', '7273', '7425']
Example Output: 74528

Example Input: ['5489', 'C', '2079', 'H', '8163', '5795', 'G', 'H', '4197', '4841', 'G', '1327', 'q', '6727', 'y', '4055']
Example Output:
42673