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: ['7799', '8163', '3389', 'x', 'k', 'm', '6085', 'f', '1131']

Output: f, k, m, x


Input: Consider 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']

Output: a, b, f, g, h, k, m, n, o, p, q, t, u, w, y, z


Input: Consider Input: ['e', 'l', '1251', 'd', 'n', '8347', '9885', '5775', '3653', '1867', 'e', '4451', '7507', '3721', '8425', 'g', 'y', 'k', '8537', '3795', '1901', '4915', 'z', 'j', '75']


Output: d, e, g, j, k, l, n, y, z