Part 1. 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.
Part 2. Example
['8129', 'a', '4245', 'y', 'm', 'a']
Answer: a, m, y
Explanation: Here, the unique alphabets in the list are 'a', 'y', and 'm', hence their sorted order is 'a, m, y'.
Part 3. Exercise
['763', '1407', '7737', '655', 'q', '8091', '6043', 'o', '839', '1101', 'v', 'd', '9191', '5533', 'w', '2297', '7953', 'f', '1699', 't', '8921', '9529', '7417', '6519', 'p', '9917', '3397', '3501', '8927', 'o', 'i', '3119', '2501', '9999', '5453', '6341', '541', 'e', '3287', 'k', 'k', 'c', '661', 'p']
Answer:
c, d, e, f, i, k, o, p, q, t, v, w