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:
['5973', 'h', '4081', 'i', '8059', 'w', 'j', '6175', 'w', '8685', '5811', 'k', 'n', '5577', '9817', 'v', '8617', 'u', 'y', '3921', 'b', '1027', '5405', 'a', '3501', '6659', 's', 'e', '157']
answer:
a, b, e, h, i, j, k, n, s, u, v, w, y


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:
['6065', 'h', '7487', 'm', '2795', 'f', 'm', '2059', 'd', 'n', '5501', '8533', '9501', 'f', 's', '5819', '5311', 'e']
answer:

d, e, f, h, m, n, s