code: func (r Billing_Item_Virtual_DedicatedHost) GetServiceBillingItemsByCategory(categoryCode *string, includeZeroRecurringFee *bool) (resp []datatypes.Billing_Item, err error) {
  	params := []interface{}{
  		categoryCode,
  		includeZeroRecurringFee,
  	}
  	err = r.Session.DoRequest("SoftLayer_Billing_Item_Virtual_DedicatedHost", "getServiceBillingItemsByCategory", params, &r.Options, &resp)
  	return
  }
docs: // This service returns billing items of a specified category code. This service should be used to retrieve billing items that you wish to cancel. Some billing items can be canceled via [[SoftLayer_Security_Certificate_Request|service cancellation]] service.
  //
  // In order to find billing items for cancellation, use [[SoftLayer_Product_Item_Category::getValidCancelableServiceItemCategories|product categories]] service to retrieve category codes that are eligible for cancellation.