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: ['b', 'd', '8153', 'u', '3695', '5317']

Output: b, d, u


Input: Consider Input: ['9351', 'v', 'h', 'z', 'g', 'f', 't', 'q', 'g', 'o', '4073', 'n', '6149', '1735', '157', 'm']

Output: f, g, h, m, n, o, q, t, v, z


Input: Consider Input: ['1529', 'a', 'z', 'v', 'r', 'm', '7731', '6645', '8585', '1273']


Output: a, m, r, v, z