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.
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Question: ['z', '5601', '5675', 'w', 's', 'z', '9213', '9563', '1699', 'p', 'g', 'm', 'c', '9279', '4481', 'p', 'n', '2389', 'c', '503', '1901', '8827', '1701', '1607', '5633', 'a', 'z', 'g', '3175', 's', 'l', 'l', '6811', '1821', '693', '8277', 'q', '8623', 'o']

Answer: a, c, g, l, m, n, o, p, q, s, w, z


Question: ['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']

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


Question: ['v', '8083', '467', 'b', 'p', 'e', 'j', 'q', 'e', '6751', '1809', 'h', 'g', 't', 'u', 'u', 't', 'p', '2611', 'n', '9467', '9581', '8173', '1447']

Answer:
b, e, g, h, j, n, p, q, t, u, v