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.
--------
Question: ['3683', 'U', 'x', '313', 'n', '3837', '3299', '2081', '2773', 'r', 'O', '257', '6647', '585', 'o']

Answer: 23475


Question: ['C', '3133', '2183', '5793', '9305', 'd', 'g', '6501']

Answer: 26915


Question: ['R', 'Z', 'y', 'b', 'O', 'm', 'v', 'z', 'x', 'Z']

Answer:
0