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: project.rb
    path of file: ./repos/rgsoc-teams/app/models
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

class Project < ApplicationRecord
  include HasSeason
  include AASM

  belongs_to :submitter, cl
    
  def mentor
    @mentor ||= begin
                  _mentor = NullMentor.new(self)
                  if _mentor.eql? submitter
                    submitter
                  else
                    _mentor
                  end