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: ['9483', '501', 'j', 'k', '3103']

A: j, k
****
Q: ['y', '8115', 'f', '5333', 'f', '3437', 'b', 'e', '5719', 'm', 'w', '95', '4863', 'k', '4895', 'a', '8179', 'm', '7919', '1731', '229', 'r', '1847', '7559', '6669']

A: a, b, e, f, k, m, r, w, y
****
Q: ['c', 'j', 'n', '8415', '8407', '8325', 'i', '3173', '3963', 'n', '2961', '8663', '3509', '6823', 'f', 'b', 'c', '5445', 'u', 'i', '7419', '7649', 's', '9603', 'h', 'k', '4123', 's', '7187', 'h', '4783', '2115', '9309', 'h', '1347']

A:
b, c, f, h, i, j, k, n, s, u
****