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:
['o', '4169', 'k', '7349', 'w', 't', '8271', '8781', '3725', '2865', '6053', 'j', 'z', '4211', '8231', '213', '6389', 'f', 'h', 'g', '9269', '4617', '4137', 'i', 'y', 'i', 'n', '4597', 'p', 'z', '3195', '3231', 'c', '1901', '1231', 'p', '4509', '2557', '3715']

Ex Output:
c, f, g, h, i, j, k, n, o, p, t, w, y, z


Ex Input:
['5971', 'x', 'c']

Ex Output:
c, x


Ex Input:
['r', '7143', 'v', '9629', '6277', 'n', '2775', '8147', 'u', 'i', '8383', '9803', 'h', '377', '7763', 'v', '7757', 'q', 'z', 'q', '8391', 'o', '2779', 'j', '4481', '8567', '6777', 'v', 's', '9475', 'l', 'x', '8139', 'e', 'n', '8733']

Ex Output:

e, h, i, j, l, n, o, q, r, s, u, v, x, z