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: ['c', '1693', 'l', 'u', 'x', '3609', 'h', '4159']

A: c, h, l, u, x
****
Q: ['h', 'g', '4563', 'v', 'm', '107']

A: g, h, m, v
****
Q: ['j', 't', '6227', '8863', 'c', 't', '3019', 'o', 'l', '9647', '7873', 's', 'h', '5491', '3151', 'y', 'p', '9977', '7803', 'm', 'z', 'p', 'u', '4103', '4731', '4161', '6679', '2271', 'd', 'w', 'a', '8319', 'b', '2841', 'm', '3705', '8769', 'o', '4137', 't', 'z', '9549']

A:
a, b, c, d, h, j, l, m, o, p, s, t, u, w, y, z
****