public new SBase getElementBySId(string id)
{
SBase ret = (SBase) libsbml.DowncastSBase(libsbmlPINVOKE.ListOfUnitDefinitions_getElementBySId(swigCPtr, id), false);
if (libsbmlPINVOKE.SWIGPendingException.Pending) throw libsbmlPINVOKE.SWIGPendingException.Retrieve();
return ret;
}