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:
['d', 'p', 'q', '5319', 'w', '4887', '6695', 't', '7711', 'l', '7597', 's', 'n', '1461', 'e', '9045', '1307', 'j']

Ex Output:
d, e, j, l, n, p, q, s, t, w


Ex Input:
['u', '8229', '2731', '6595', '4675', 'n', 'a', '7361', '7401', '7273', 'b', '279', '5539', '7919', 'j', 'x', '9521', '8837', '7391', 'h', 'x', 'h', '7283', 't', '3769', '2317', '9131', 'h', 'y', 'c', '1625', 'm', 'e', 'a', '8437', '7543', 'p', '2451', 'k', 'r']

Ex Output:
a, b, c, e, h, j, k, m, n, p, r, t, u, x, y


Ex Input:
['t', 'y', 'm', 's', 'w', '9151', 'x', 'm', '9589', '5059', 'b', 'g', 'z', '8165', 'r', 'b', '4565', 'o']

Ex Output:

b, g, m, o, r, s, t, w, x, y, z