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: ['4271', 'N', 'M', '5239', '7037', 'x', 'U', 's', '7107', '4163', 'f', '3607', '6155']
Example Output: 37579

Example Input: ['Q', '1767', '5523', 'I', '933', 'h', '2189', 'f', '7795', 'X', 'M', 'G', '1215', 'W', '8619']
Example Output: 28041

Example Input: ['W', '8593', '9427', '9931', '8919', 'X', 'B', '8861', '1933', 'Z', 'V', '3427', 'S', '8717', 'd', '1593', '7659', 'Q', 'n']
Example Output:
69060