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: ['4743', '9687', '2887', '4413', 'r', 'w', '2355', 'l', 'd', '453', 'o', 'm', '4351', '5881', '3963', 'g', 'r', 'z', 'q', '7555', 'y', '9555', '405', 'n', 'l', '6733', '1763', 'v', '9925', 'y', '633', '827', 'w']

SOLUTION: d, g, l, m, n, o, q, r, v, w, y, z

PROBLEM: ['6627', '8037', 'q', 'e', 'j', 'p', '9613', '9317', 'm', 'm', '5345', 'f', '8105', '5665', '4175', '4793', '3707', 'i', 'b', '6745', '747', '8329', '1481', 'b', '8949', 'n', '4803', '1359', '3533', 'f', '543', '3003', '6943']

SOLUTION: b, e, f, i, j, m, n, p, q

PROBLEM: ['8959', 'j', '7495', '381', 'r']

SOLUTION:
j, r