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.

[EX Q]: ['t', '7469', 'Y', 'N', '8137']
[EX A]: 15606

[EX Q]: ['2013', 'S', 's', '9353', 'b', 'u', '6687', '5429', '3545', '7269']
[EX A]: 34296

[EX Q]: ['G', 'p', 'g', '6307', '6773']
[EX A]:
13080