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 concatenate all elements of A from the ith element to the jth element, and print the resultant string. 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.
Input: 12, 20, ['v', 'K', '5907', 'B', '9811', 'B', 'h', '9955', 'W', 'v', '7605', '4133', 'f', '7101', 'K', '8269', 'b', 'L', 'D', '9151', '2731']

4133f7101K8269bLD9151