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: ['w', '1367', '5389', '9515']

A: w
****
Q: ['z', 'l', 's', 'f', 'j', 'x', '1125', 'd', '37', '5009', '9187', 'b', '8683', '8841', 'y', '9955', '1571', 'm', '347', '3679', '5797', '2133', 'g', 'u', '9817', '6347', '2067', '1927', '167', '4215', '45', 't', 'd', '6599', '4751', 'g', 'l', 'u', '7881', 's']

A: b, d, f, g, j, l, m, s, t, u, x, y, z
****
Q: ['c', 'v', 'a', 's', 'r', 'j', 'u', 'a', '9103', '8443', 'e', 'g', '7681', 't', 'a', '6719', 'y', 'o', 'x', 'm', '5341', '2611', 'o', 'x', 'a', 'h', 'w', '3243', 'q', '8557', '6545', '381', 'g', 'm']

A:
a, c, e, g, h, j, m, o, q, r, s, t, u, v, w, x, y
****