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', '3809', 'l', 'k', '1929', '7963', 'n', 'u', '2125', 'g', 'o', '8325', 'o', 'h', 'y', '3025', 'e', 'e', 'c', 'x', '8445', '4979', 'z', 'f', '4201', '4765', 'g']
c, e, f, g, h, k, l, m, n, o, u, x, y, z

['333', 'b', '261', 'k', 'p', '7861']
b, k, p

['t', 'w', 'l', 'p', '5141', '4749', '5653', 'h', 'h', 'g', 'q', 't', '3061', '7575', '3037']

g, h, l, p, q, t, w