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.

[EX Q]: ['9271', '6393', '6005', 'x', '2301', '3999', 'p', 'z', 'j', '1033', '7555', 'r', 'r', 'y', '8917', '5939', '4031', 'e', '8095', 'g', '6095', 'a', '4133', '6471', '2129', '8021', '1093', 't', '8805', '545', 'k', '3249', 'l', '1561', '9909', 's', '1963', 'o']
[EX A]: a, e, g, j, k, l, o, p, r, s, t, x, y, z

[EX Q]: ['d', '1989', '6365', 'y', 'm', '1245', '7539', 'm', '3787', '6987', 'e', 'e', 'y', '9577', 'b', '5', '8179', 'x', '2853', '6337', 'w', 'f', 'b', 'q', '563', '6077', '1133', 'x', '6045']
[EX A]: b, d, e, f, m, q, w, x, y

[EX Q]: ['i', '2417', '1395', '8569', '5613', '8969', '2559', '5301', '7251', '7599', '377', 'w', '9323', '7497', '9489', 'a', '9353', '5781', '4651', '3743', 'k']
[EX A]:
a, i, k, w