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: ['n', 'w', '6735', '3427', '6115', 'q', '7851', '3645', 'g', '6825', '6515', '4885', 'z']

Answer: g, n, q, w, z


Question: ['o', '5503', '5837', '4539', '7631', 'm', '2641', 'p', '7901', '8117', 'z', '3373', '3215', 'v', 'a', '5949', 'w', '9049', 'd', 'a', 'l', 'v', 'l', 'n', 'w', 'r', 'j', '9031', '9609', '4209', 'c', '7453', '5855', '2883', '5941', 't', '4283', 'x', 'x', 'n', 'c']

Answer: a, c, d, j, l, m, n, o, p, r, t, v, w, x, z


Question: ['d', '1925', '1899', 'a', '3991', '4483', '2957', '5661', '8585', '8901', 'u', 'q', 'c', 'g', '1213', 's', '2687', '9953', 'b', 'v', '9773', 'u', 'i', '5343', 'a', '8045', 'q', '9787', '9143', '3341', 'h', 'a', '7305', 'p', '3341', '9509', 'h', '9099', '5329', 'v', 'y', '3853']

Answer:
a, b, c, d, g, h, i, p, q, s, u, v, y