Instructions: 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.
Input: ['J', '3909', '9609', 'I', 'n', '1595', '4159', '1181', '9847', '9855', 'b', 'o', 'I', 'k', '7759', '7921', '817']
Output:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
56652