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: ['x', 'i', 'r', '6011', 't', 'f', 'b', 'i', '8367', '4051', '1459', 'f', '5583', '9609', 'l', 'q', 'g', '8443', 'o', '8697', '7053', '8325', 'k', '7021', 'q', 'm', '6899', '9981', '8985', 'i', 'j', '8043', 'k', '535', '7603', '7629', 'k', '2779', 'g', '2049', 'x', 'd', '8527', 'k', 'q']

Answer: b, d, f, g, i, j, k, l, m, o, q, r, t, x


Question: ['9421', 'h', 'z', '4373', 'l', 'm', '7221', 'd', 'm', 'w', '8967', '6295', '9345', 'b', 'u', '3867', 'h', 'f', '7633', '1409', '2253', '7209', '4339', 'e', '2445', '3469', '9113', 'd', '855', '1969', 'q', 'u', '2655', 'r', 'z']

Answer:
b, d, e, f, h, l, m, q, r, u, w, z