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: ['m', '8127', '7519', '4543', '2809', '9855', 'n', '6241', 'w', 'w', 'q', 'w', 'p', '8599', '7819', '3817', 'm', 'q']

A: m, n, p, q, w
****
Q: ['p', '3981', 'e', '5949', 'p', '4075', '1919', 'w', 'r', '8059', '4303', 'f', '5201', '2255', '2737', '7395', '8809', 'j', 'z', 'n', '4797']

A: e, f, j, n, p, r, w, z
****
Q: ['x', 'g', 'q', 'p', 'l', '6963', 't', 'f', '1707', 'i', '2049', '4125', '5407', 'l', '2583', '3499', '7527', '6727', '8289', 'g', '1695', '8829', 'z', '3855', '9603', 'z', '5063', '6325', '9949', 'e', 'z', '9391', 'w', 't', '6433']

A:
e, f, g, i, l, p, q, t, w, x, z
****