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.
--------
Question: ['2913', 'b', 'j', '7591', 'O', 's', '5589', '4995', '7503', 'U', 'S', 'C', '6797']

Answer: 35388


Question: ['R', 'J', 'z', 'o', '1121', '7247', '8987', 'u']

Answer: 17355


Question: ['i', 'z', '1779', '2701', 'P', '2945', 'H', 'i', '873', 'p', 'd', 'L', '2845', '3053', '7365', '4181', 'Y']

Answer:
25742