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.

['j', 'y', '9907', 'a', '5715', 'l', '9817', '1949', '2697', '2255', '9571', '8957', '9329', '6055', 'z', 'q', '1185', '4593']
a, j, l, q, y, z

['2161', '8009', '3057', 'r', '3897', 'd', 'j', '2727', 'b', '3231', 'i', '9227', '393', '5799']
b, d, i, j, r

['1899', '8335', 'h', 'q', '5131', 'y', 'o', '9649', 't', 'x', 'v', '4439', '8467', 'z', 'u', 'b', '9139', '1387', 'q', 'p', 'u', 'c', '9121', 'o', 's', '257', 'b', 'i', '8393', 'a']

a, b, c, h, i, o, p, q, s, t, u, v, x, y, z