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:
['749', 'r', 'a', 's', 't', '5905', 'm', 'd', '8437', '4583']

Ex Output:
a, d, m, r, s, t


Ex Input:
['2161', '8009', '3057', 'r', '3897', 'd', 'j', '2727', 'b', '3231', 'i', '9227', '393', '5799']

Ex Output:
b, d, i, j, r


Ex Input:
['8511', '1935', '1165', '213', 'p', '3927', 'a', '2617', '1783', '2481', 'f', '5911', 'u', 'e', 'q', '7495', '5257', 'u', 'c', 'c', '2675', 'q', '9015', '207', 'h', '6263', '1039', 'x', '3027', '2403', 't', '4013', 'b', '4491', 'j', '1409', 'z', '8665', 's', 'h']

Ex Output:

a, b, c, e, f, h, j, p, q, s, t, u, x, z