code: func (r Billing_Item_Virtual_DedicatedHost) GetAssociatedBillingItemHistory() (resp []datatypes.Billing_Item_Association_History, err error) {
  	err = r.Session.DoRequest("SoftLayer_Billing_Item_Virtual_DedicatedHost", "getAssociatedBillingItemHistory", nil, &r.Options, &resp)
  	return
  }
docs: // Retrieve A history of billing items which a billing item has been associated with.