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]: ['N', 'V', 't', 'X', 't', 'M']
[EX A]: 0

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

[EX Q]: ['5199', 'h', 'T', 'T', 'l', '1661', 'p']
[EX A]:
6860