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:
['2915', '6033', '5541', '4685', '1263', '6701', 's', '7269', 'g', '8033', '8171', '6917', 'l', '2913', '447', 'g', 'a', 'z', 'o', '7563', '5385', '5259', '5067', '4869', '2653', '6925', '7001', '8553', 'x', '1243', '9131', '5037']

Ex Output:
a, g, l, o, s, x, z


Ex Input:
['q', 'g', 's', 'g', 'z', '987', '777']

Ex Output:
g, q, s, z


Ex Input:
['f', '7485', '5245', '8661', '9939', '2349', 'l', 'x', 'm', '1827', 't', 'd', '123', 'l', 'v', 'm', '8421', '1737', '3457', 'o', 'k', '6133', 'd', '8335', '9469', 'k', 'o', '9153', 'j', 'e']

Ex Output:

d, e, f, j, k, l, m, o, t, v, x