def simple(name = nil)
      workbook.add_worksheet(name: name || 'Sheet 1') do |sheet|
        yield sheet, workbook.predefined_styles if block_given?
        sheet.add_row
      end
    end
def simple(name = nil)
      workbook.add_worksheet(name: name || 'Sheet 1') do |sheet|
        yield sheet, workbook.predefined_styles if block_given?
        sheet.add_row
      end
    end
Creates a simple workbook with one sheet.

 Predefines multiple styles that can be used to format cells.
 The +sheet+ and +styles+ are yielded to the provided block.

 See Axlsx::Workbook#predefined_styles for a list of predefined styles.