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', 'a', '6931', 'c', 'u', 'z', '9713', 'v', 'm', 'e', 'k', 'o', '9705', 'a', '5373', 'c', '2983', '8097', 'h', '3039', 'g', 'f', 'n', 'v', '853', '8227', '7573', 'j', 'h', 'k', 'o', 'k', '8897', 'd', 'g', 'd', 'd', '4039']
a, c, d, e, f, g, h, j, k, m, n, o, u, v, z

['o', 'l', 'm', 't', '4487', '1019', '9903', 'c']
c, l, m, o, t

['l', 'w', '4921', '2933', '3801', 's', 'b', '3105', 'i', 'f', 'i', '1145', '3745', 'x', 's', 'y', '3737', 'i', 'a', 'g', 'b', '7747', 'q', '6603', '555', '8059', '8305', 'n', '8027', 'w', '7701', 'a', '5255', '225', 'v', 'i', 'm', '6379', 'u', '1639', '4551', '1317', 'n', 'd']

a, b, d, f, g, i, l, m, n, q, s, u, v, w, x, y