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.

[EX Q]: ['2103', '7937', 'v', '7641', '6609', '269', '4463', '4333', 'c', '8407', '4883', '6283', 'a', '8643', '3365', '1929', 'v', 'o', '2107', '7453', '9157', '5581', '5187', 'f', 'k', '8227', '6295', 'b', 'y', '4995', '1187', 'k', 'n', 'p', 'z', '8165', 'n', '7345', 'l']
[EX A]: a, b, c, f, k, l, n, o, p, v, y, z

[EX Q]: ['n', '7489', 'n', 'n', '9787', '7829', 'n', '3481', 'v', 'l', '8927', 'c', 'm', 'd']
[EX A]: c, d, l, m, n, v

[EX Q]: ['f', 'e', 'l', 'c', 'z', '5835', 'c', '103', 'd', 'l', 'f', 'a', 'c', 'z', '3953', 'r', '3217', 'g', '3225', '6825', 'f', '593', 'g', 'r', 'l', 'g', '8469', 'g', 'r']
[EX A]:
a, c, d, e, f, g, l, r, z