$var1={
        'stud.xml'={ 
                   '24'=>'<address>
                           <streetname="xxxx"/>
                            <housenum="138"/">
                           </address>'
                     '20'=>'<address>
                           <streetname="xxxx"/>
                            <housenum="110"/">
                           </address>'
                         }
         'pav.xml'={ 
                   '26'=>'<address>
                           <streetname="xxxx"/>
                            <housenum="138"/">
                           </address>'
                     '27'=>'<address>
                           <streetname="xxxx"/>
                            <housenum="110"/">
                           </address>'
                         }
                         .
                         .
                         .
                 }