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: ['3145', 'C', '7725', 'k', 'z']

SOLUTION: 10870

PROBLEM: ['1305', '1673', 'w']

SOLUTION: 2978

PROBLEM: ['6913', 'X', '9157', 'o', '7973', 'h', '5205', 'c', 'E', '4047', 'p', 'e', 'P', 'u', 'y', 'N', '6183', '2247', '5041']

SOLUTION:
46766