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.

['t', 't', 'p', '3245', 'x', 'g', 'i', 'u', '2599', '8613', 't', 'v', 'p', '5635', 'y', '9567', '5193', '8617', 'q', 'f']
f, g, i, p, q, t, u, v, x, y

['3651', 'c', 'm', '7123', '2981', '9649', 'o', '2181', 'h', '8577', 'a', '5027', 'x', 'u', '1039', '347', '8219', 'c', '1063', '8885', 'f', 'd', '3067', '2509', 'i', 's', '5509', '2003', 'h', '8869', 'x', 'd', '5141', 'h', 'i', 'b', 'o']
a, b, c, d, f, h, i, m, o, s, u, x

['879', 'y', 'f', '5287', 'w', 'f', '8183', '9741', 'k', '3651', 'y', 't', '959', '4431', 'b', '607', 'u', 'r', 'u']

b, f, k, r, t, u, w, y