module ActiveModel::SerializerSupport::ClassMethods

def active_model_serializer
  @active_model_serializer ||= "#{self.name}Serializer".safe_constantize
end

def active_model_serializer
  return @active_model_serializer if defined?(@active_model_serializer)
  begin
    @active_model_serializer = "#{self.name}Serializer".constantize
  rescue NameError => e
    raise unless e.message =~ /uninitialized constant/
  end
end