code: func (r Billing_Invoice) GetZeroFeeItemCounts() (resp []datatypes.Container_Product_Item_Category_ZeroFee_Count, err error) {
  	err = r.Session.DoRequest("SoftLayer_Billing_Invoice", "getZeroFeeItemCounts", nil, &r.Options, &resp)
  	return
  }
docs: // no documentation yet