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]: ['z', '3219', '6399', '2357', '7597', '357', 'k', 'k', 'u', 'd', '6115', 'w', '2921', '8809']
[A]: d, k, u, w, z


[Q]: ['4009', 'y', '9077', 'p', 'q', '6711', '6443', '5491']
[A]: p, q, y


[Q]: ['3459', '8753', 's', '9737', 's', 'e', 'a', '8589', 'r', '691', 'd', '6599', 'f', '9015', '4279', 'x', '7335', '9163', 'g', 'u', '341', 'n', '6595', '7339']
[A]:
a, d, e, f, g, n, r, s, u, x