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: ['6249', '1235']

Output: -1


Input: Consider Input: ['o', 'd', '6495', '5211', '341', 'v', '385', 'v', 'g', 'v', 'l', '7631', '2675', 't']

Output: d, g, l, o, t, v


Input: Consider Input: ['r', 'x', 'p', '3799', '6635', 'q', 's', 'd', 'a', '8501', '4439', 'a', 'o', '8117', '1609', 'n', 'f', '1555', 'c', 'q', '6067', '2599', 't', 's', '1929', 'r', 'e', '5805', 'y', '3077', 'i', '9361', '2027', '4383', '1353', 'h', 'q', 's', 'x', 'c']


Output: a, c, d, e, f, h, i, n, o, p, q, r, s, t, x, y