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: ['5345', 'f', '6605', 's', 'q', 'w', 'p', 'o', 's', 'u', 'i', '7339', '8379', 'h', '9547', 'b']

A: b, f, h, i, o, p, q, s, u, w
****
Q: ['w', '8777', 'y', 'e', '8015', 't', 'w', '53', '9149', 'e', 'k', '1837', 'b', 's', '4007', '4905']

A: b, e, k, s, t, w, y
****
Q: ['4747', '8209', '4867', '7243', 'z', 't', 'm', '7779', 'w', '1089', '8011', 's', '1901', 'e', 'a', 'n', '8025', 'r', '4843', '5657', '1193', 'u', '3653', '1933', '1767', '43', '5719', '1465', 'j', 'n', 't', '3799', 's', '1557']

A:
a, e, j, m, n, r, s, t, u, w, z
****