code: def register_to_payment(order_class, **kwargs):
      
      global Payment
      global Order
  
      class Payment(PaymentFactory.construct(order=order_class, **kwargs)):
          objects = PaymentManager()
  
          class Meta:
              ordering = ('-created_on',)
              verbose_name = _("Payment")
              verbose_name_plural = _("Payments")
  
      Order = order_class
  
      # Now build models for backends
  
      backend_models_modules = import_backend_modules('models')
      for backend_name, models_module in backend_models_modules.items():
          for model in models_module.build_models(Payment):
              apps.register_model(backend_name, model)
      return Payment
docs: A function for registering unaware order class to ``getpaid``. This will
      generate a ``Payment`` model class that will store payments with
      ForeignKey to original order class
  
      This also will build a model class for every enabled backend.