def parse(node)
      node.xpath('*').each do |node_child|
        case node_child.name
        when 'p'
          @elements << DocxParagraph.new(parent: self).parse(node_child)
        when 'r'
          @elements << ParagraphRun.new(parent: self).parse(node_child)
        when 'tbl'
          @elements << Table.new(parent: self).parse(node_child)
        end
      end
      self
    end
def parse(node)
      node.xpath('*').each do |node_child|
        case node_child.name
        when 'p'
          @elements << DocxParagraph.new(parent: self).parse(node_child)
        when 'r'
          @elements << ParagraphRun.new(parent: self).parse(node_child)
        when 'tbl'
          @elements << Table.new(parent: self).parse(node_child)
        end
      end
      self
    end
Parse SDTContent object
 @param node [Nokogiri::XML:Element] node to parse
 @return [SDTContent] result of parsing