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: ['e', 'c', '4241', '2685', 'o', '9859', 'z', '2647', 'b', 'c', 'y', '1985', '5985', '5709', '6655', 'q', 'z', '9933', '6817', '6477', '1837', 'x', 'p', '9251', '3787', 'v', '5741', 'e', 'p', '493', '5949', '5519', 'v', 'g', '1403', 'z', 'h', 'z']

Answer: b, c, e, g, h, o, p, q, v, x, y, z


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: ['7133', '737', '5415', 's', '4691', 'u', 'i', '8719', '8347', '5249', 'q', 'd', 's', 'y', '3831', '689', 'd', 'b', '1165', 't', 'h', 'n', 't', '2511', '7919', 'w', '4077', '2475']

Answer:
b, d, h, i, n, q, s, t, u, w, y