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]: ['U', '5607', 'Q', 'j', 'I', '3745', '3031']
[EX A]: 12383

[EX Q]: ['w', '7301', '9411', 'z', 'g', 'X', '1045', 'l', 'F', 'M', 'R', '7957', 'e', '5145']
[EX A]: 30859

[EX Q]: ['q', '8785', '5801', '6187', 'H', 'N', '5651', 'k', '1703']
[EX A]:
28127