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: ['3191', '2655', '239', '2585', '3369', '7815', '5919', '8269', '5633', 'x', '8085', '2909', 'y', '2465', 'i', '1579', 'u', '2371', 'l', '1949', '51', 'e']

A: e, i, l, u, x, y
****
Q: ['6709', 't', 'n', 'k', '991', 'a', '8899', '3563', '527', 'm', '4599', '6679', 'm', 'x', 'f', 'o', '3275', 'x', '677', 'b', '3329', '3593', '5183', '5753', 'u', '6045', '2607', 'y', '9873']

A: a, b, f, k, m, n, o, t, u, x, y
****
Q: ['4471', '6639', '6533', 'n', '2517', 'g', '927', '1621', '6361', 'w', 'l', '5211', 'z', '8011', 'b', 'w', 'e', '7097', '2039', '6185', 'o', '107', 'v', '7963']

A:
b, e, g, l, n, o, v, w, z
****