old_contents: ##############################################################################
  # For copyright and license notices, see __manifest__.py file in module root
  # directory
  ##############################################################################
  from odoo import models, fields, api
  
  
  class SaleGlobalDiscountWizard(models.TransientModel):
  
      _name = "sale.order.global_discount.wizard"
  
      # todo implement fixed amount
      # type = fields.Selection([
      #     ('percentage', 'Percentage'),
      #     ('fixed_amount', 'Fixed Amount'),
      #     ],
      #     'Type',
      #     required=True,
      #     default='percentage',
      #     )
      discount1 = fields.Boolean(
          string='Discount 1',
      )
      discount2 = fields.Boolean(
          string='Discount 2',
      )
      discount3 = fields.Boolean(
          string='Discount 3',
      )
      discount1_amount = fields.Float(
          '(%)',
      )
      discount2_amount = fields.Float(
          '(%)',
      )
      discount3_amount = fields.Float(
          '(%)',
      )
      amount = fields.Float(
          required=False,
      )
  
      @api.multi
      def confirm(self):
          self.ensure_one()
          order = self.env['sale.order'].browse(
              self._context.get('active_id', False))
          for line in order.order_line:
              if self.discount1:
                  line.discount1 = self.discount1_amount
              if self.discount2:
                  line.discount2 = self.discount2_amount
              if self.discount3:
                  line.discount3 = self.discount3_amount
          return True
  
new_contents: ##############################################################################
  # For copyright and license notices, see __manifest__.py file in module root
  # directory
  ##############################################################################
  from odoo import models, fields, api
  
  
  class SaleGlobalDiscountWizard(models.TransientModel):
  
      _name = "sale.order.global_discount.wizard"
  
      discount1 = fields.Boolean(
          string='Discount 1',
      )
      discount2 = fields.Boolean(
          string='Discount 2',
      )
      discount3 = fields.Boolean(
          string='Discount 3',
      )
      discount1_amount = fields.Float(
          '(%)',
      )
      discount2_amount = fields.Float(
          '(%)',
      )
      discount3_amount = fields.Float(
          '(%)',
      )
      amount = fields.Float(
          required=False,
      )
  
      @api.multi
      def confirm(self):
          self.ensure_one()
          order = self.env['sale.order'].browse(
              self._context.get('active_id', False))
          for line in order.order_line:
              if self.discount1:
                  line.discount1 = self.discount1_amount
              if self.discount2:
                  line.discount2 = self.discount2_amount
              if self.discount3:
                  line.discount3 = self.discount3_amount
          return True
  
subject: Remove commented code.