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.

['m', '5005', 'y', 'h', 'w', '3609', 'p', '2539', '3307', 'p']
h, m, p, w, y

['8739', 'v', 'm', '6277', 'l', 's', '109', '8057', '3835', 'd', 'u', 'f', 'w', 'd', 'p', '7705', '3643', '4455', 'u', 'p', 'u', '9407', 'g', 'w', '595', 'z', '6827', '6879', 'w', 'w', '6973', 'm', 'e', '1553', 'v', '3529', '8953', '3903', '5713', '8249', 'e', '1113', 'b', 't', 'r']
b, d, e, f, g, l, m, p, r, s, t, u, v, w, z

['9289', 'g', 'm', 'e', 's', '9825', '1981', '4935', '4771', '4615', 'u', '1523', 'k', '7469', 'e', 'e', 'o', 'f', 'r', 'd', 'b', 'w', '3277', 'g', 'f', '8427', '3137', '4483', 'u', '9223', 'g', '4853', 'r', 'k']

b, d, e, f, g, k, m, o, r, s, u, w