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: ['3117', 'i', 'd', '7537', 'i', 'q', '4649', '7263', '3655', 'd', 'x', '8569', 'g', '2389', '3933', '7099', '563', '3055', '9941', 'm', 'c', '3529', '3577', 'x', 's', 's', '6153', '1731', '9679', 'f', '8839', '5183', '5', '6433']

Answer: c, d, f, g, i, m, q, s, x


Question: ['i', '9575', '8995', 'm', 'o', '3015', '4005', '6909', '7195', '3361', 'j', '5253', '9523', '8879', '5861', 'e', 'y', 'e', '1525', 'i', '807', '8469', '3333', '4017', '2237', '3387', 'o', '643', 'p', '7129', '6243', 'y', '4913', 'z', 'f', '6909', 'f', '4347', '7227', 'o', 's', '9909', '8611']

Answer: e, f, i, j, m, o, p, s, y, z


Question: ['4993', 'n', '7115', 'f', 'd', 'q', '249', '3203', 'w', '5689', '4103', '7129', '603', 'e', 'z', '5571', '3241', '6029', '2721', '8451', 'o', '7841', 'p', '6271', 'r', 'b', '9481', '4045', 'v']

Answer:
b, d, e, f, n, o, p, q, r, v, w, z