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.

[EX Q]: ['6143', 'y', '5505', '9813', 'r', 'v', 'u', '8681', '2387', 'u', 'o', 'm', '9793', 'm']
[EX A]: m, o, r, u, v, y

[EX Q]: ['i', '9575', '8995', 'm', 'o', '3015', '4005', '6909', '7195', '3361', 'j', '5253', '9523', '8879', '5861', 'e', 'y', 'e', '1525', 'i', '807', '8469', '3333', '4017', '2237', '3387', 'o', '643', 'p', '7129', '6243', 'y', '4913', 'z', 'f', '6909', 'f', '4347', '7227', 'o', 's', '9909', '8611']
[EX A]: e, f, i, j, m, o, p, s, y, z

[EX Q]: ['4629', 'd', 'h', 'd', 'c', '7999', 'p', '261', 'q', 'h', 'e', '1943', '167', 'h', '7869', '8573', '5321', 'u', '6215', 'e', '8605', '9421', 'v', '7265', 'e', 'u', '5361', 'n', 't', 'w']
[EX A]:
c, d, e, h, n, p, q, t, u, v, w