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: ['2161', '8009', '3057', 'r', '3897', 'd', 'j', '2727', 'b', '3231', 'i', '9227', '393', '5799']

Output: b, d, i, j, r


Input: Consider Input: ['5499', 'v', '6507', 'w', 'c', '8431', '8861', '5391', '4765', '4295', '1865', '485', '7255', '1205', 'p', 'w', 'q', '6833', '959', 'a', 'i', '2599', '7779', 'h', '9651', 'g', 'r', 'e', 'u', '4511', '1587', '5601', '8287', '5685', 'u', 'g', '2853', 'p', 'k']

Output: a, c, e, g, h, i, k, p, q, r, u, v, w


Input: Consider Input: ['t', '2055', '5823', '2571', 'm', '4463', 'i', 'j', '6447', '2121', '4371', 'j', 'z', 'n']


Output: i, j, m, n, t, z