将ActiveRecord对象包装为PORO。如何获取所有属性？

class User < ActiveRecord::Base
  # ActiveRecord model definition
end

class UserPORO
  attr_accessor :id, :name, :email

  def initialize(attributes = {})
    @id = attributes[:id]
    @name = attributes[:name]
    @email = attributes[:email]
  end
end

# 获取ActiveRecord对象的所有属性
user = User.find(1)
attributes = user.attributes

# 将ActiveRecord对象包装为PORO对象
user_poro = UserPORO.new(attributes)

# 访问PORO对象的属性
puts user_poro.id
puts user_poro.name
puts user_poro.email