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: ['1749', 'i', 'w', 'j', '3171', '1999', '1037', '4937', '7013', '3593', '287', 'o', 'i', 'j']

A: i, j, o, w
****
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: ['u', '6679', 'm', '9221', '7063', '4615', '7405', '2657', 't', '4061', 'u', 'e', 'o', '1627', '7269', 'w', 'c', 'y', 'g', '5019', 'j', 'w']

A:
c, e, g, j, m, o, t, u, w, y
****