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, 21, ['9559', '3287', 'd', '9059', '9873', '7785', 'y', 'M', '6949', 'n', '3163', 's', 'C', '8997', 'u', '5605', '2991', '113', 'I', '6353', 'D', '2977', '3087', '7943', 'D']

sC8997u56052991113I6353D