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', 'J', 'z', 'o', '1121', '7247', '8987', 'u']
[A]: 17355


[Q]: ['z', 'U', '6817', 's', '3731', 'M', 'I', '1095', 'l', '5993', '5207', 'e', 'L', '5361', 'v', 'g', '1963', '4829', '9541', '8261']
[A]: 52798


[Q]: ['u', '9575', 'S', '1237', 'Y', 'Y', '8199', 't', 'z', 'A', 'P']
[A]:
19011