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: ['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']

Output: b, c, d, e, h, l, m, o, p, q, s, u, v, x


Input: Consider Input: ['315', '9975', '3013', 's', '6131', 'e', 'e', 'u', 'a', '1729', 'g', 't', 'y', 'f', '7523', 'e', 'g', '489', 'm', 'p', 'f', 'e', '2077', 'e', 'g', 'c', 'l', '6389', 'k', 'b']

Output: a, b, c, e, f, g, k, l, m, p, s, t, u, y


Input: Consider Input: ['2381', 'y', '6631', '5839', 'r', 'm', 'z', 'b', '4663', '595', '7771', '5305', '5087', '3317', '3125', '9551', '4343', '5121', 'm', 'i', '131', '8401', '5379', '1775', 'u', '1125', '9793', '4123', 'h', '1613']


Output: b, h, i, m, r, u, y, z