TASK DEFINITION: In this task, you are given an input list A comprising of numbers and alphabets. You need to extract and sort the unique alphabets in the list. The alphabets in the input list will only be in lowercase. Return -1 if there is no alphabet in the input list.
PROBLEM: ['2047', '4403', 'g', '3017', '1627', 'v', 'r', '2237', '5513', 'o', 'v', '7229', '9801', 'j', '443', 'z', 'q', 'y', '7447', '1659', '3411', '55', '5153', '9921', '2195', '1075', '8187', 'p', 'x', 'h', 'y', 't', 'a', 'r', 'f']

SOLUTION: a, f, g, h, j, o, p, q, r, t, v, x, y, z

PROBLEM: ['o', '369', 'z', '5721', 'w', 'v', '4973', '7773', 'k', '3071', '5103', '425', '4239', '7977', 'n', 'i', 'k', '8117', '9843', 'n', 'd', '1353', 'h', 'd', 'v', 'z', 'j', '8727', '6997', 'x', '767', '4331', 't']

SOLUTION: d, h, i, j, k, n, o, t, v, w, x, z

PROBLEM: ['j', '917', 'w', 't', '8873', '1431', '8059', '7041']

SOLUTION:
j, t, w