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.

[Q]: ['r', '3139', 'C', 'L', '7335', 'v', '9861', 'F']
[A]: 20335


[Q]: ['O', 'j', 'Z', 'u', '7427', '4225', '3139', '9993', '9945', '3639', 'h', 'j', 'f', '6511', 'e', '4607', '2741', '4743']
[A]: 56970


[Q]: ['3141', 'B', 'F', '6265', '69', '639', '2219', 'P', 'T', '5951']
[A]:
18284