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', 'd', '6495', '5211', '341', 'v', '385', 'v', 'g', 'v', 'l', '7631', '2675', 't']

Answer: d, g, l, o, t, v


Question: ['a', 'p', 'y', 'l', 'l']

Answer: a, l, p, y


Question: ['j', '1835', '5479', '2039', '1769']

Answer:
j