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: ['g', '8591', '4463', '2189', '7901', '1457', 'f', 'i', '9031', 'r', '5519', '3955', 'd', '2093', 'c', 'y', '6591', '6463', 'h', '4371', '111', 'p', '3221', '4185', 'p', '8761', 'w', 'p']

SOLUTION: c, d, f, g, h, i, p, r, w, y

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

SOLUTION: j, t, w

PROBLEM: ['g', 'm', '8395', '1077', '9031', 'y', '8007', 'd', 'g', '2365', 'o', '7553', '9499', '8697', '8751', 'q', 'j', 'z', '8717', '7991', 'r', 'm', 'e', 'w', '5203']

SOLUTION:
d, e, g, j, m, o, q, r, w, y, z