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.

Ex Input:
['5039', '2227', 't', 'o', '3313', 'm', 'v', '637', '6773', 'v', 'c', 'l', 'y', 'u', '3823', '9669', 'k', 'h', '3589', 'b', 'i', '3833', 's', 'm', '8201', 'u', '3143', 'k', '4111', '9769', '425', '4339', '209', 'c', 'c', '669', '8201', 'u', '7443', '2387', '6919', 'b', 'b', '2873']

Ex Output:
b, c, h, i, k, l, m, o, s, t, u, v, y


Ex Input:
['8281', '4831', '1329', 'g', 'e', '8879', 'n', 's', 'x', 'j', '6305', 'j', '921', '3677', '5107', 'n', 'j', '9285', 'a', '5329', '6671', 'c', '9283', 'l', 'a', '7907', 'q', '7605', '855', '6477']

Ex Output:
a, c, e, g, j, l, n, q, s, x


Ex Input:
['s', 'q', 'f', '1059', '7047', 'i', '899', '8673', '77', 'm', '9861', '4235', '1819', '4213', '2425', '4463', '4271']

Ex Output:

f, i, m, q, s