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: ['2097', '7815', 'f', '1705', '7553', 'C', 'n', '7091', '1253', 'z', '9229', 'H', 'N', '6481', 'H', 'M', 'G', '4527', '8537']

Answer: 56288


Question: ['r', '6537', '3001', '7879']

Answer: 17417


Question: ['6321', 'M', 'd', '3673']

Answer:
9994