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: ['1063', 'f', 'm', 'i', 'x', 'i', 'd']

A: d, f, i, m, x
****
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: ['2149', 'x', '4101', '6435', 'q', 'h', 'j', 'z', 'o', 'b', 'k', '8147', 'e', '3813', 't', '165', 'l', '99', '895', 'v']

A:
b, e, h, j, k, l, o, q, t, v, x, z
****