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: ['i', '4447', 'g', 'o', 'j', 'p', 'l', 'q', 'o', '8777', 'r', 'v', '961', '6083']

Output: g, i, j, l, o, p, q, r, v


Input: Consider Input: ['2527', '9123', '8717']

Output: -1


Input: Consider Input: ['4915', 'm', 'g', 'd', '9363', 'b', 'i', '7249', 'h', '6355', 'c', '9683', '2647', 'z', 'n', 'f', '711', '5939', '5565', '3759', 'i', 'j', '5197', '4495', 'u', '4269', 'k', 'q', 't', 'w', '7651', 'b', 'o', '3589', '8973', '8987', '2203', '4899', 'c', 'k', '7989', 'x']


Output: b, c, d, f, g, h, i, j, k, m, n, o, q, t, u, w, x, z