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.
--------
Question: ['9113', '3625', 'u', '8189', '3649', '259', '5539', '1583', 'g', '4037', 'y', 'v', '8337', 'd', 'q', 'j', 'c', 'h', 'p', '1601', 'z', 'c', 'n', '1767', '1679', '1805', 'm', '4469', '2487', '6015', '973']

Answer: c, d, g, h, j, m, n, p, q, u, v, y, z


Question: ['t', 'h', '6141', 'g', 'f', 'z', 'n', 'b', 'k', '9059', 'y', 'p', '4289', '2683', 'a', '3267', 'w', 'p', 't', '3623', '7759', 'a', 'o', 'm', '9815', 'q', 'u', '8051', '6871']

Answer: a, b, f, g, h, k, m, n, o, p, q, t, u, w, y, z


Question: ['5355', '1273', '1611', '9377', '9109', '1037', 's', '8145', '4437', '353', 'v', '6553', '2851', '4515', '7657', '361', 'c', 'n', 't', 'x', 'i', '633', '6785', '3153', 'v', 'f', '5765', '4413', '2767', '8237', '5897', 'b', '8999', 'x', '7677', '8379', 'q', 'o', 'i', '6947', '9563', 'c', '7707', 't']

Answer:
b, c, f, i, n, o, q, s, t, v, x