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: ['2453', 'r', 'd', '8499', 't', 's', 'h', 'a', 'm', '9271', 'g', '2599', '6209', 'o', 'i', '4069', 't', '6793', '7679', '6643', '7359', 'm', 'f', 'w', '775', '3347', '6161', '9745', 'i']

Answer: a, d, f, g, h, i, m, o, r, s, t, w


Question: ['d', 'g', '9019', '9987', '8713', '9513', 'a', '2043', 'd', '5817', 'w', 'd']

Answer: a, d, g, w


Question: ['2753', '1677', 'j', '5123', '7897', '7899', '1561', '675', '9295']

Answer:
j