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: ['8495', 'p', 'j', 'm', 'n', '9115', '1183', 'r', 'r', '8735', 'a', 'i', 'k', 'p', '8927', 'r', '9283', '9563', 'g', '2503', 'h', '1091', '5257', 'a', '3061', '2835', 'l', 'w', 'j', '7617', '8793', '7463', 'h', '8467', '7337', 'b', '4655', 'd']

Answer: a, b, d, g, h, i, j, k, l, m, n, p, r, w


Question: ['c', '1693', 'l', 'u', 'x', '3609', 'h', '4159']

Answer: c, h, l, u, x


Question: ['3593', '8097', '4585', '145', 'f', '4171', '7263']

Answer:
f