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.

Q: ['f', '217', '449', 't', 'j', '4097', '5561', '8317', '647', 'u', 'b', '7833', 'r', '9011', 'z', '2753', '2183', 'z', 'o', 'g', '7541', 'b', '8795', '327', 'v', 'e', 't', 'l', '4909', 'k', '7681', 'r']

A: b, e, f, g, j, k, l, o, r, t, u, v, z
****
Q: ['7055', '2573', '1713', 'x', 'm']

A: m, x
****
Q: ['4841', 'y', 'b', 'u', '1709', '9645', '9303', 'b', '6849', 't', '1021', '6041', 'k']

A:
b, k, t, u, y
****