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', 'v', 'B', 'Y']
Example Output: 0

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: ['L', 'u', '8151', 'H', '7281', '429']
Example Output:
15861