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]: ['4213', '3595', '7937', 'y', '5723', 'v', 'b', '7007']
[EX A]: b, v, y

[EX Q]: ['w', 'o', 'l', '5331', 'k', '9325', '6759', '7931', '8185', 'w', 'h', 'h', 'x', '4357', '6845', 'v', 'o', '8401', 'u', 'g', 'f', 'j', 'j', '2493', '4753', 'c', 'm', '1469', '4307', 'm', '2737', 'n', 'y']
[EX A]: c, f, g, h, j, k, l, m, n, o, u, v, w, x, y

[EX Q]: ['3503', 'o', 'g', 'p', 'k', 'x', '1527', '675', '4217']
[EX A]:
g, k, o, p, x