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.

Q: ['w', '6291', '3939', '9569', 'u', '1635', '3359', '8335', 'n', '2799', '7359', 'k', 'm', '2817']

A: k, m, n, u, w
****
Q: ['5785', 'c', 'f', '7087', 'd', '9225', 'm', 'g', '4639', '7165', '3445', '3813', 'p', 'i', '719', 's', 'g', '6423', '9563', 'w', 'm', '8659', '8809', '4105', '3923', '465', '5637', '5547', 'h', 'v', '9453', '4009']

A: c, d, f, g, h, i, m, p, s, v, w
****
Q: ['6293', 'q', '2171', '6461', '9149', '2191', '1881', 'j', 'y', 'x', 'z', '2203', '4877', 't', 'c', '3237', '1901', 'u', '1551', 'n', '9575', '5681', 'd']

A:
c, d, j, n, q, t, u, x, y, z
****