Manage Exceptions

I begin to use Data Zoom and is very good and simply but I have a problem. How I can manage an exception in get_item invocation.

This is the code:

#set( $list_dett = $web.lists.get_item("TEST") )

## Build a CAML query Anagrafica dettaglio

#set( $caml_dett = '<Where><Eq><FieldRef /><Value>' )#set( $caml_dett = "$!{caml_dett}$ID_Utente_Int" )#set( $caml_dett = "$!{caml_dett}</Value></Eq></Where>" )#set( $query_dett = $SPUtility.CreateSPQuery($caml_dett) )## Get the list items dettaglio#set( $listItems_dett = $list_dett.GetItems($query_dett) ) #foreach($item in $listItems_dett)… The web part work correctly but if I try to open the web part with a user that don’t have permission in the List “TEST” the message is: Exception
Invocation of method 'get_item' in Microsoft.SharePoint.SPListCollection threw exception System.ArgumentException : Valore non compreso nell'intervallo previsto. Someone have any idea how  manage the error.

Thanks