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', '1099', 'r', '8995', 'o', '2909']

Answer: o, r


Question: ['e', '8391', '7065', '6141', '3335', 't', 'i', 'c', '1791', '6333', 'b', 'z', '1621', 'e', 'h', 'u', 'o', 'q', '3195', '6507', '3253', 'c', '2067', '3917', '7111', 'r', 'j', 'd', '3987', '9139', 'm', '981', 'l', 'f', '2417', 'w', '9983', 'h', 'd', '6021', 'a', 'f']

Answer: a, b, c, d, e, f, h, i, j, l, m, o, q, r, t, u, w, z


Question: ['y', '8853', 'l', 'r', 'j', '5625', '8419', '4107', 'd', '2499']

Answer:
d, j, l, r, y