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: ['r', 'n', '7583', '8697', '7927', 'l', '5003', '1363', 'p', 'e', 'q', '6227', '6915', '8619', '9011', 'n', '3063', '3799']

Answer: e, l, n, p, q, r


Question: ['3821', '385', 'y', '8457', '6623', 'g', '5923', 'a', '7193', 'v', 'm', '8915', 'v', '5873', 'p', 't', 'w', 'y', '3617', 'h', 'w', 'j', '8047', 'u', '2271', 'v', 'a', '2181', 's', '1051', 'b', 'a', '9967', '987', 'z', '2255', '6349', '1249', '1397', 'q']

Answer: a, b, g, h, j, m, p, q, s, t, u, v, w, y, z


Question: ['1615', 'g', 'm', 'v', '6987', '2969', '6415', 'y', 'n', '7533', '767', '5369', 'z', '7581', 'e', '3881', 'r', '4275', '7247', '565', '1665']

Answer:
e, g, m, n, r, v, y, z