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.
--------
Question: ['7441', '7967', '2011', '1383', 'i', '3623', 'b', 'y', 'e', '1593', 'r', 'a', 'd', 'b', '6159', '3931', '989', '435', 'o', 'y', 'j', 'w', '7669', 'y', '5781', 'u', '531', '7467', '3971', '8139', 'w', 'a', '5113', '9461', '8377', '7431', '6975', '6055', '7307', 'v']

Answer: a, b, d, e, i, j, o, r, u, v, w, y


Question: ['s', 'c', 'e', '2457', '9413', 'r', '9949', 's', 'z', 'e', 'a', 'o', '7207']

Answer: a, c, e, o, r, s, z


Question: ['a', '7733', 'n', '3377', '1073', 'q', 'e', '7927', 'v', 'u', '2561', 'l', '3339', '2693', 'v', '1165', 'r', '2711', '5859', '2141', 'h', 'x', '2755', '4745', 'l', '7253', '1273', '1163', 'g']

Answer:
a, e, g, h, l, n, q, r, u, v, x