OP solved it, closing

It's hard to help in general without solving (part of) the problem for you. You'd better ask more concrete questions. I think it's clear enough from the description: if you see how encode works, then you understand what decode should do: just reverse the encoding process. Clear doesn't mean easy, but this is a 3kyu for a reason, meaning it is supposed to be part of the relatively hard katas.

A "#" means that u have to delete(or backspace) the letter before it. Example : a#b = b since ur deleting "a"

Five consecutive numbers, in any order, 1 could be seen as 1 or 7.

I don't know what you are trying to do, but you must not import the tests in your solution, nor use a it decorator like you are doing in your function. Just stick with the solution set up:

def likes(names):
    pass