Definition: 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: ['9421', 'h', 'z', '4373', 'l', 'm', '7221', 'd', 'm', 'w', '8967', '6295', '9345', 'b', 'u', '3867', 'h', 'f', '7633', '1409', '2253', '7209', '4339', 'e', '2445', '3469', '9113', 'd', '855', '1969', 'q', 'u', '2655', 'r', 'z']
Output:
b, d, e, f, h, l, m, q, r, u, w, z