def each_field
      return to_enum(:each_field) unless block_given?

      self.class.all_fields.each do |field|
        value = self[field.name]
        yield(field, value)
      end
    end
def each_field
      return to_enum(:each_field) unless block_given?

      self.class.all_fields.each do |field|
        value = self[field.name]
        yield(field, value)
      end
    end
Iterate over every field, invoking the given block