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.

['6643', '6757', 'h', '1033', 's', 'c', '2003', 'p', '5483', 'f']
c, f, h, p, s

['p', 'f', 'h', '1977', '6221', 'i', 'a', 'l', '5225', '8059', 'c', 'w']
a, c, f, h, i, l, p, w

['9753', '3083', '5225', 'k', 'y', '3145', 'd', 'l', '7051', '1477', '6299', 'f', '2655']

d, f, k, l, y

