TASK DEFINITION: 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.
PROBLEM: ['w', '7301', '9411', 'z', 'g', 'X', '1045', 'l', 'F', 'M', 'R', '7957', 'e', '5145']

SOLUTION: 30859

PROBLEM: ['D', 'C', '7295', 'g', 'j', '1387', 'O', '4701', 'B', 'd', 'W', 'b', 's', 'n', 'n', '4917', '2941', '1825', 'x']

SOLUTION: 23066

PROBLEM: ['2831', '1829', '9961', 'c', '6973', '6499']

SOLUTION:
28093