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: ['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: ['6709', 't', 'n', 'k', '991', 'a', '8899', '3563', '527', 'm', '4599', '6679', 'm', 'x', 'f', 'o', '3275', 'x', '677', 'b', '3329', '3593', '5183', '5753', 'u', '6045', '2607', 'y', '9873']

Answer: a, b, f, k, m, n, o, t, u, x, y


Question: ['j', '4525', 'g']

Answer:
g, j