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]: ['N', 'O', '2635', '8891']
[A]: 11526


[Q]: ['X', 'f', 'p', 'R', 'N']
[A]: 0


[Q]: ['e', '5273', '5505', '4573', '497', '2769', 'c']
[A]:
18617