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', '9215', 'n', 'p', '4815', '8757', 'm', '1755', 'c', 'z']

A: c, i, m, n, p, z
****
Q: ['1197', '305', 's', '1113', 'n', '2207', 'e', '227', '2833', '607', '3049', 'v', '4615', 'a', 'k', 'r', 's', '3571', 'f', '4215', 'f', '8985', '5559', '4111', 'u', '1433', '1943', '8831', 'w', 'x', 'o', '9023', 'u', 'y', 'p', 's', 'h', '8877', 'p', 'n', '8903', '5811']

A: a, e, f, h, k, n, o, p, r, s, u, v, w, x, y
****
Q: ['k', '2943', 's', 'i', '531', 'm', 'g', '2677', '8293', '5249', '5459', 'j', 'z', '1843', 'i', '3543', 'q', '1765', 'w', '8507', '7981', '9399', '803', '255', '751', 'k', '5423', '8023', '8243', '4635', 'v', 'v', '6415', '5751', '9417', 'i']

A:
g, i, j, k, m, q, s, v, w, z
****