TASK DEFINITION: In this task, you are given inputs i,j, and A, where i and j are integers and A is a list. You need to return the sum of all the numerical elements in the list A between the positions i and j (including positions i and j). Return 0 if no numerical element is present in the list between the given ranges. i and j will be non-negative, and will always have a value less than the length of A. i will always be less than j.
PROBLEM: 1, 7, ['Y', 'n', '8993', 'X', '7211', 's', 't', 'R', 'm', 'L', '9559', 'K', 'j', '791']

SOLUTION: 16204

PROBLEM: 1, 20, ['N', '3757', '4835', '557', 'n', '3381', '3229', '9715', 'O', 'J', '5215', 'Q', '7867', 'W', '5159', '1571', '2911', '8907', 'J', 'b']

SOLUTION: 57104

PROBLEM: 6, 18, ['I', 'K', 'S', 'x', '8407', 'r', 'Y', '5219', 'v', '6671', 's', 'G', 'R', '9803', '3197', '1889', 'a', '2753', '3321']

SOLUTION:
29532

