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: ['4993', 'n', '7115', 'f', 'd', 'q', '249', '3203', 'w', '5689', '4103', '7129', '603', 'e', 'z', '5571', '3241', '6029', '2721', '8451', 'o', '7841', 'p', '6271', 'r', 'b', '9481', '4045', 'v']

Answer: b, d, e, f, n, o, p, q, r, v, w, z


Question: ['i', 's', 'f', 'i', '2293', '245', '4983', 'h', 'h', '6203', '8703', '1613', 'h', 'o', '3635', '8069', '2829', '1939', 'u', 'm', '5305', 'n', 'k', '9367', 'u']

Answer: f, h, i, k, m, n, o, s, u


Question: ['v', 'y', '9825', '6211', '7897', 'f', 'y', '2343', 'h', '6095', 'b', '1037', 'b', 'h', 'h', 'c', '275', '8387', 'g', '4331', 'e', 'p', '6923', '4003', '2143', '7349', '9233', '7127', '9937', '863', 'h', 'f', '2509', 'h', '339', 'z', 's', 'g', 'h', '5147', 'i', 'o']

Answer:
b, c, e, f, g, h, i, o, p, s, v, y, z