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: ['d', 'r', '7769', '2159', 's', '3269', '5527', 'l', 'z', 'e', '5165', 'x', 'x', '8273', 'g', 'm', '7609', '4015', '6403', '3753', 'y', 'h', 'l', 'i', '389', 'm', 'u', '6845', 'r', 'c', '7571', '3355', '9755', 'n', '4625', 'p', '5645', '1703', '4439', 't', '8431']

A: c, d, e, g, h, i, l, m, n, p, r, s, t, u, x, y, z
****
Q: ['i', '1191', '5581', '2527', 'g', '9795', '519', 'u', '8389', '9793', 'k', '5733', '7125', '7835', 'j', '855', 'd', 'd', '6555', '3211', 'l', 'o', 'b', '523', 'x', 'j', '1707', '4161', '7171', 'h', 'h', 'm', 'h', '2443', 'e', '649', '951', 'n', 'h']

A: b, d, e, g, h, i, j, k, l, m, n, o, u, x
****
Q: ['7773', '1939']

A:
-1
****