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: ['1429', '7763', '9737', 'l', '1865', 's', '9871', 'e', 'c', 'q', '2727', 'v', 'p', 'd', 'p', '6771', 'c', '7051', 'e', 'b', 'd', 'o', '7427', 'x', 'e', 'm', 'u', '4887', '1649', 'u', 'h', '5249', 'e', '7579', '8549']
Example Output: b, c, d, e, h, l, m, o, p, q, s, u, v, x

Example Input: ['t', 'c', 'r', '4459', 'o', '1407', 'x', '1515', '331', 'm', '1535', 'p', 'u', 'g', '2513', 'o', '7827', '8149', 'd', 'z', 'q', '5655', 'x', '9997', '2809', 'g', 'h', '6309', 'a', 'j', '9773', '2115', 't', '9113', 'q', 'o', '427', 's', '3815', '5423', 's', 'n', 'i', 'o', '3643']
Example Output: a, c, d, g, h, i, j, m, n, o, p, q, r, s, t, u, x, z

Example Input: ['571', 'b', 'w', '9485', 'k', 'z']
Example Output:
b, k, w, z