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]: ['3433', '6955', 'Q', 'E', '3557', 'S', '2931', '9879', 'S', 'f', 'Q']
[A]: 26755


[Q]: ['5331', 'f', '2865', '6019', 'U', 'm', 'g', 'n', 'Y', 'A']
[A]: 14215


[Q]: ['r', 'Z']
[A]:
0