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 Input:
['7301', '7999', 'x', 'r', '6881', 'e', '609', 's', '7495', 'a', 's', '1961', 'q', 'x', '373', '6289', '4847', '5969', 't', '5487', '7639', '9039', '2395', 'b', 'd', '1447', 's', '8137', 's', '443', 'f', 'z', '4823', 'k', 'i', 'o', '4739', 'w', 'f', '8853', 'a']

Ex Output:
a, b, d, e, f, i, k, o, q, r, s, t, w, x, z


Ex Input:
['8357', 'x', 'w', '287', 'z', '2733', '1757', 'w', 'g', '1393', '7201', '4931', 'k', '5185', 'x', '6313', '2255', 'z', 'v', '3593', '6191', '4423', 'm', 'k', '3209', '3559', 'c', 'n', 'm', '5461', '2997', '235', '4045', '6597', 'v', 'e', 'p', 'c', 'k', 'd', '5529', '6241', 'u', 'f', '8067']

Ex Output:
c, d, e, f, g, k, m, n, p, u, v, w, x, z


Ex Input:
['1187', '5513', '7277', 's', 'i', '9485', 'l', '3121', '235', 'd', '1161', 'o', 'f', '8355', 'h', 't', '2005', '7837', '4669', '3009', 'j', 'v', 'h', 'r', 'k', 'x', '9543', 'k', 'c', '4855', 'e']

Ex Output:

c, d, e, f, h, i, j, k, l, o, r, s, t, v, x