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.

Example Input: ['t', 'h', '6141', 'g', 'f', 'z', 'n', 'b', 'k', '9059', 'y', 'p', '4289', '2683', 'a', '3267', 'w', 'p', 't', '3623', '7759', 'a', 'o', 'm', '9815', 'q', 'u', '8051', '6871']
Example Output: a, b, f, g, h, k, m, n, o, p, q, t, u, w, y, z

Example Input: ['u', '9249', 'u', 't', 'm', 'm', 'n', 'w', '8617', '2729', 'i', 'l', '2971', '3227', 'b', '9017', '4711', 'i', 't', 'r', 'a', 'a', '1701', '6397', '4535', '9167', '6039', '6111', '849', 'p', '8197', '2645', '5147', 'u', 'l', '7419', 'w', 'w', 'k', 'x', 'c', '3377', '4015', '1297', 'f']
Example Output: a, b, c, f, i, k, l, m, n, p, r, t, u, w, x

Example Input: ['7177', '5333', 'f', '3041', 'v', '9289', 'n', '7671', '2507', '4915', '4759', '4937', 'r', 'k', 'n', 'a', '9497', 'q', 'b', '2863', '6009', 'n', 'q', 'u', 'r', 't', '8791', 'm']
Example Output:
a, b, f, k, m, n, q, r, t, u, v