def parse(node)
      node.attributes.each do |key, value|
        case key
        when 'count'
          @count = value.value.to_i
        end
      end

      node.xpath('*').each do |node_child|
        case node_child.name
        when 'xf'
          @xf_array << Xf.new(parent: self).parse(node_child)
        end
      end
      self
    end
def parse(node)
      node.attributes.each do |key, value|
        case key
        when 'count'
          @count = value.value.to_i
        end
      end

      node.xpath('*').each do |node_child|
        case node_child.name
        when 'xf'
          @xf_array << Xf.new(parent: self).parse(node_child)
        end
      end
      self
    end
Parse CellXfs data
 @param [Nokogiri::XML:Element] node with CellXfs data
 @return [CellXfs] value of CellXfs data