initialize_dup

# File activerecord/lib/active_record/attribute_methods/dirty.rb, line 44
      def initialize_dup(other) # :nodoc:
        super
        @attributes = self.class._default_attributes.map do |attr|
          attr.with_value_from_user(@attributes.fetch_value(attr.name))
        end
        @mutation_tracker = nil
      end