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', 'g', '1649', 'a', '2115', '6763', 'r', 't', 'l', 's', 'y', '5659', 'a', 'b']

A: a, b, g, l, r, s, t, w, y
****
Q: ['p', 'k', 'i', '753', 'u', 'm', '3817', '1597', 'l', 'm', 'a', 'i', 'b', 's', 'c', '2561', 'x', '5363', '1173', '8657', '2033', 'b', 'p', '3093', 'k', '6535', '307', '9925', 'b', 'q', 'q']

A: a, b, c, i, k, l, m, p, q, s, u, x
****
Q: ['l', 'p', 'j', 'i', '6347', '3261', '3381', '753', '6121', '8373', '3787', 'b', '9669', 's', 'r', 'u', 'c', '8031', 'i', 'u', '4775', 'd', 'k', 'c', '2429', '2841', 'd', 'i', '7121', 'k', 'l', '1291', 'i', '1561', '2615', '15', '1011', 'n', 'z', '3883', 'd', '7181']

A:
b, c, d, i, j, k, l, n, p, r, s, u, z
****