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', 't', '2135', '8397', '6361', '389', '2253', 'x', 'p', '4833', '5785', 'x', '1811', '9639', '5739', '175', '3231', '5931', 'r', 'c', 'g', 'h', 'p', '909', 'p', '587', 'a', 'a', 'h', 'q', 's', '5945', '4911', 't', 'h', '7517', 'p', '3177', 'h', 'u', '3577', '7055', 'l']

Answer: a, c, f, g, h, l, p, q, r, s, t, u, x


Question: ['o', '4169', 'k', '7349', 'w', 't', '8271', '8781', '3725', '2865', '6053', 'j', 'z', '4211', '8231', '213', '6389', 'f', 'h', 'g', '9269', '4617', '4137', 'i', 'y', 'i', 'n', '4597', 'p', 'z', '3195', '3231', 'c', '1901', '1231', 'p', '4509', '2557', '3715']

Answer: c, f, g, h, i, j, k, n, o, p, t, w, y, z


Question: ['7625', 't', '6709', '9325', '8421', 'e', 'l', '4059', 'x', '2203', 'y', '4329', 'y', '6807', '1501', '9985', '8063', '4841', '797', '1081', 'g', '4391', '8753', '1037', 'l', 'd', 'j', 'x', '1203', 'r', 'b', '9029', 'y', 'v', 'h', '7579', '2863', 'g', 'd', 's', 't', 'd']

Answer:
b, d, e, g, h, j, l, r, s, t, v, x, y