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.

Q: ['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']

A: f, h, i, k, m, n, o, s, u
****
Q: ['8527', 'p', '4697', '8415', 'v', 'l', '2669', '2649', '4349', '4201', 'r', '7573', '2041', 'f', '8047', 'u', 'm', 'm', 'j', '5695']

A: f, j, l, m, p, r, u, v
****
Q: ['407', 't', '7671', 'a', '1751', '3049', '871', 'm', 't', 'l', '8937', '7505', '343', '2855', '2035', 'h', 'u', '1405', 'e', 'a', 'n', '1931', 'o', 'p', '2801', 'd', '1065', 'c', 'c']

A:
a, c, d, e, h, l, m, n, o, p, t, u
****