instruction:
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.
question:
['t', 'x', '1699', '8727']
answer:
t, x


question:
['1223', 'h', 'a', 'o', 'v', '2535', 'g', '6267', 'w', '9625', '7961', '9577', '7611', '5655', 'p', 'j', 's', '2141', '4101', 'l', '4367', '9383', 'n', '5965', '9097', '7571', 'p', 'u', 'x']
answer:
a, g, h, j, l, n, o, p, s, u, v, w, x


question:
['y', 'h', 'y', '9', 'e', 'z', 'c', 'c', 'l', '8049', '8853', '8689', '8621', '6787', 'x', '7355', 't', 't', 'r', '7045', 'c', '1827', 's']
answer:

c, e, h, l, r, s, t, x, y, z