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: ['l', 'g', 'd', 'p', '8163', '6643', 'o', 'p', 'm']
Example Output: d, g, l, m, o, p

Example Input: ['g', 'x', 'x', 'a', 'w', 'a', 'v', 'x', 'i', '3927', 'n', '1631', 'l', 'd', 'd', 'p', 'r', 'p', 'd', 't', '1645', '9043', '9119', 'r', '9751', 'v', '4549', '9465', '9601', 'f', '3501', '2593', 'i', '8195', 'm', 'i', '6295', 'i', '3305', 'p']
Example Output:
a, d, f, g, i, l, m, n, p, r, t, v, w, x