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.

['8319', 'f', 'w', 'w', 'v', '6521', '4503', 'b', 's', 'b', '9651', 'k', '4635', '2195', '7537', '6839', 'i', 'd', 'b', '205', 'q', '7333', 'q', '5129', '4921', 's']
b, d, f, i, k, q, s, v, w

['i', '4447', 'g', 'o', 'j', 'p', 'l', 'q', 'o', '8777', 'r', 'v', '961', '6083']
g, i, j, l, o, p, q, r, v

['3587', 'd', '6161', '9341', 'b', 'e', 'a', '4769', 't', 'l', 'i', 'c', '4283', '8083', '3333', 't', 'b', 'w', 'a', 'u', '5431', 'v', 'o', '3191', '5601', '7085', 'm', '5099', 'k', '3881', '7641', '7495']

a, b, c, d, e, i, k, l, m, o, t, u, v, w