TASK DEFINITION: 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.
PROBLEM: ['l', '7111', 'd', 'e', 'h', 'z', 'x', '5673', 'v', '8255', 'i', 'z', 'c', 'i', '4287', 'q', '9293', '9137', 'p', 'n', 'o', 'n', '7883', '6453', '7355', '8769', 'y', '9153']

SOLUTION: c, d, e, h, i, l, n, o, p, q, v, x, y, z

PROBLEM: ['5345', 'f', '6605', 's', 'q', 'w', 'p', 'o', 's', 'u', 'i', '7339', '8379', 'h', '9547', 'b']

SOLUTION: b, f, h, i, o, p, q, s, u, w

PROBLEM: ['263', '155', '311', 'e', '929', 'l', '9411', '913', '6233', '4503', 'f']

SOLUTION:
e, f, l