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.

['5345', 'f', '6605', 's', 'q', 'w', 'p', 'o', 's', 'u', 'i', '7339', '8379', 'h', '9547', 'b']
b, f, h, i, o, p, q, s, u, w

['2453', 'r', 'd', '8499', 't', 's', 'h', 'a', 'm', '9271', 'g', '2599', '6209', 'o', 'i', '4069', 't', '6793', '7679', '6643', '7359', 'm', 'f', 'w', '775', '3347', '6161', '9745', 'i']
a, d, f, g, h, i, m, o, r, s, t, w

['m', 'z', 't', 'u', '4815', '2455', 'y', '3999', '5451', '6557', 'r', '6775', '6499', 'b', '6061', '5973', 'x', 'z', 't', '7573', 'l', 'w', '6985', 'q', 'd', 's', 'k', '4549', '2801', 'q', '9897', '3415', '2233', '7001', 'd', '547', 'g', '2661', 'l', 'f', 'e', '1147', 'p', '1441']

b, d, e, f, g, k, l, m, p, q, r, s, t, u, w, x, y, z