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: ['T', '721', '6555', 'g', 'y', 'U', '3053', 'A', '9663']
Example Output: 19992

Example Input: ['3565', 'z', '8811', 'z', 'U', '113', 'I', '1307', '135', 'V', 'P', '5183', '2505', '4863', '1113', 'A', '7575', '827', 'B']
Example Output: 35997

Example Input: ['p', 'Q', 'a', '903', '2877', 'u', '289', '8885']
Example Output:
12954