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: ['x', 'b', '1467', 'y', '2101', 'y', 'm', '2745', 'z', '429', '7523', 'e', 'f']

A: b, e, f, m, x, y, z
****
Q: ['9113', '3625', 'u', '8189', '3649', '259', '5539', '1583', 'g', '4037', 'y', 'v', '8337', 'd', 'q', 'j', 'c', 'h', 'p', '1601', 'z', 'c', 'n', '1767', '1679', '1805', 'm', '4469', '2487', '6015', '973']

A: c, d, g, h, j, m, n, p, q, u, v, y, z
****
Q: ['7209', 'w', 'u', '5581', '8901', 'z', '179', 'b', '359', 'u', '7905', 't', '7115', '4933', 'x', 'd', 'q', '8863', 'z', 'g', 'c', 'm', 'l', '7427', '9373', '3321', '1331', '2783', 'v', 'x', 'z', '5937']

A:
b, c, d, g, l, m, q, t, u, v, w, x, z
****