You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: rating_methods.rb
    path of file: ./repos/moebooru/app/models/post
    
    the code of the file until where you have to start completion: module Post::RatingMethods
  attr_ac
    
  def pretty_rating
    case rating
    when "q"
      "Questionable"

    when "e"
      "Explicit"

    when "s"
      "Safe"
    end