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.

['3127', '9253', '5667', '9453']
-1

['477', '3931', 'g', '5967', 'm', '9845', '1607', 'a', '1749', 'k', 'j', '7945', '9125', 'v', 'n', 's', '5185', '1117', '17', 'x', '4149']
a, g, j, k, m, n, s, v, x

['3527', '8731', 'z', 'l', 'w', '4043', '9639', '1367', 'c', '3353', 'e', 'n', '9711', '339', '3047', 'e']

c, e, l, n, w, z