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: ['f', 'j', '9195', '3155', '2855', '5333', '5263', '9279', '687', 'e', '3055', '7233', '13', 'j', 'p', 'i', '8327', 'm', 'h', '3977', 'h', '7997', 'a', 'h', '4661', 'x', '8237', 'a', '5009', 'o', 'p', 'z', '2293', 'q', 'p', '5469', 'k', 'q', 'b', 'n', '1967', '4991']

Answer: a, b, e, f, h, i, j, k, m, n, o, p, q, x, z


Question: ['o', '4167', 'b', '1651', '8327', '9219', 'o', 'v', '5841', '6057', 'i', 'q', 'o', 'r', 'a', '7069', 'y', 'h', 'd', '3775', 'j', 't', '3663', '55', '7117', 'e', 'u', 'm', '931', '5777', '8773', '4891']

Answer: a, b, d, e, h, i, j, m, o, q, r, t, u, v, y


Question: ['7239', 'a', '5563', '5621', 'i', 'b', '9659', 'r', 'p', '9661', 'f', '7825', '1323']

Answer:
a, b, f, i, p, r