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.

['d', '1625']
d

['n', 'g', 'u', '2873', 'k', '4411', 'w', '8179', 'w', 'w', 'f', 'g', 'e', '7837', '3055', 'z', 's', '6037', 'n', '1479', 'c', '5311', 'i', 'w', 'z', '1891', '9663', 'y', 'f', 'h']
c, e, f, g, h, i, k, n, s, u, w, y, z

['u', 'a', 'e', 'v', 'y', 'j', '3113', '749', '6399', 'v', 'f', 'u', 'l', '3261', '8029', '2071', '8085', '8035', 'q', 'z', 'l', '5039', 'x', 'u', 's', '3391', '9721', '8031', '5455', 'm', 'y']

a, e, f, j, l, m, q, s, u, v, x, y, z