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.

Input: Consider Input: ['k', 'r', 'f', '4369', 'z', 'z', 'l', '143', 'r', '707', '9167', 'g', '1749', 'i']

Output: f, g, i, k, l, r, z


Input: Consider Input: ['z', '5601', '5675', 'w', 's', 'z', '9213', '9563', '1699', 'p', 'g', 'm', 'c', '9279', '4481', 'p', 'n', '2389', 'c', '503', '1901', '8827', '1701', '1607', '5633', 'a', 'z', 'g', '3175', 's', 'l', 'l', '6811', '1821', '693', '8277', 'q', '8623', 'o']

Output: a, c, g, l, m, n, o, p, q, s, w, z


Input: Consider Input: ['7227', '5231', 'l', '9243', '6777', '1235', '3585', 'v', '421', '1725', 'b', 'r', '6039', '9261', '6013', 'm', 'k', '791', 'q', '269', 'e', 't', 'a']


Output: a, b, e, k, l, m, q, r, t, v