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: user_finder.rb
    path of file: ./repos/chaskiq/app/services
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

module UserFinder
  extend ActiveSupport::Concern

  def find_user
    # TODO: , change th
    
  def find_user
    # TODO: , change this when leads can have mail
    if @user_data.blank? || @user_data[:email].blank?
      visitor = get_user_by_session
    else
      @app.app_users.find_by(email: @user_data[:email])
    end