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]: ['a', 'a', 'b']
[A]: a, b


[Q]: ['h', '6865', '4019', '8571', 'y', '5575', '7835', '9537', 'n', '875', 't', 'a', 's', '2769', 'p', '1607', 'n', '4087', '961', '7869', '5085', '2131', '4867', 'j', 'h', 'y', '3105', '6609', 's', 'l', '3399', '5013']
[A]: a, h, j, l, n, p, s, t, y


[Q]: ['a', 'h', 'c', 'j', 'k', '9765', 'a', '1291', 'm', '5585', '8493', 'r', '959', 'a', 'g', '3449', '4755', '4573', 'n', 'w', '5047', '9553', 'h', '3517', 'o', '5665', 'c', '1661', 'f', 'p', 'i', '4537', 'i', 't', '9319', 'e', 'q', 'v', 'd', 's', 'o', 'j', 'w', '3363']
[A]:
a, c, d, e, f, g, h, i, j, k, m, n, o, p, q, r, s, t, v, w