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.
--------
Question: ['e', 'n', 'y', 'f', 'l', 'h', '455', 'y', '591', 'm', '9041', 'b', 'b', 'o', '4215', '5009', 'o', 'a', '4369', 'u', '6911', '4825', 't', 'k', '6063', '2939']

Answer: a, b, e, f, h, k, l, m, n, o, t, u, y


Question: ['8527', 'p', '4697', '8415', 'v', 'l', '2669', '2649', '4349', '4201', 'r', '7573', '2041', 'f', '8047', 'u', 'm', 'm', 'j', '5695']

Answer: f, j, l, m, p, r, u, v


Question: ['2509', '9459', '639', '8327', 'j', 'a', '799', 'z', '3233', 'i', '5115', '7355', 'j', '5529', '9981', '5115', 'q', 't', '1073', 'n', 'x', 'q', 'l', 'i', 'z', '2043', '4001', 'm', 'h', 'q', '711', 'g']

Answer:
a, g, h, i, j, l, m, n, q, t, x, z