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.

[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']
[A]: a, b, c, f, k, l, n, o, p, v, y, z


[Q]: ['u', 'd', '4193', '5687', 'p', 'r', '7787', 't']
[A]: d, p, r, t, u


[Q]: ['p', 'o', 's', '4157', '501', '8887', 's', 'n', '4161', '9227', '1443', '3935', 'd', '9133', 'b', '2043', '7361', 'a', '5529', '451', 'u', '2381', 'b', '8853', '5667', 'x', '197', 'y', 'p', '379', 'c', '901', '8651', 'g', 't', '5987']
[A]:
a, b, c, d, g, n, o, p, s, t, u, x, y