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: ['8301', 'd', 'p', 'l', 'm', '9099', 'o', '8045', 'e', 's', 't', '8853', 'v', '6375', 'q', '2505', 's', '4219', '3587', 'g', '651', '7129']

Answer: d, e, g, l, m, o, p, q, s, t, v


Question: ['2047', '4403', 'g', '3017', '1627', 'v', 'r', '2237', '5513', 'o', 'v', '7229', '9801', 'j', '443', 'z', 'q', 'y', '7447', '1659', '3411', '55', '5153', '9921', '2195', '1075', '8187', 'p', 'x', 'h', 'y', 't', 'a', 'r', 'f']

Answer: a, f, g, h, j, o, p, q, r, t, v, x, y, z


Question: ['5161', 'q', '393', '5947', '2877', '3701', '6409', 's', '9121', 'i', 'c', '8377', '3027', 'b', '5143', 'u', '3131', 'e', '8605', 'k', '9821', 'v', '2093', 'k', '1897', '2833', '9747', 'o', 'a', '3995', 'h', 'n', 'y', '4235']

Answer:
a, b, c, e, h, i, k, n, o, q, s, u, v, y