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: ['3651', 'c', 'm', '7123', '2981', '9649', 'o', '2181', 'h', '8577', 'a', '5027', 'x', 'u', '1039', '347', '8219', 'c', '1063', '8885', 'f', 'd', '3067', '2509', 'i', 's', '5509', '2003', 'h', '8869', 'x', 'd', '5141', 'h', 'i', 'b', 'o']

Output: a, b, c, d, f, h, i, m, o, s, u, x


Input: Consider Input: ['m', '6761']

Output: m


Input: Consider Input: ['m', 'c', '5131', 'r', 't', '311', 't', 'c', 'e', '9269', '2621', 'd']


Output: c, d, e, m, r, t