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: ['61', '5695', 'u', '253', 'n', '1035', 'd', '3017']
Example Output: 10061

Example Input: ['m', 'e', 'W', 'N', '4459', '693', '3765', '2641']
Example Output: 11558

Example Input: ['4089', 'D', '6075', '9519', '3805', '3217', '8725', '3461', 'A', 'S', '2207', 'g', '7329', 's', '4011', '4441', 'a', 'T']
Example Output:
56879