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: ['8005', 'q', 'w', 'a', 'f', 'o', '6017', '7591', 'm', 'p', 'z', 'q', 'u', 'o', 'd', '6043', 'f', '3575', 'r', '2885', 'o', '3141', '621', '2375', 't', '5397', 'h', 'b', 'i', '3785', '1551', 'i', '8879', 'g', '5237', '7111', '2057', '1743', '9895', '2613', 'i', 'z', '677']

SOLUTION: a, b, d, f, g, h, i, m, o, p, q, r, t, u, w, z

PROBLEM: ['w', '491', 'x', 'u', 'z', 'q', '5411', '7629', '8261', '8629', '1441', '5139', 's', 'm', '6463', 'u', 'z']

SOLUTION: m, q, s, u, w, x, z

PROBLEM: ['5263', 'k', '8201', 's', 'h', '6175', 'y', 'v', '35', 'd', 'i', '8347', '7133', 'o', '127', '5317', '8039', 'g', '3901', '5251', 'j', 'g', '4831', 'w', '2791', 'd', 'r', 'd', '1029', 'q']

SOLUTION:
d, g, h, i, j, k, o, q, r, s, v, w, y