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: ['T', '721', '6555', 'g', 'y', 'U', '3053', 'A', '9663']

Answer: 19992


Question: ['4161', 'E']

Answer: 4161


Question: ['3187', 'g', 'x', 'u', 'R']

Answer:
3187