     BEGIN:VCALENDAR     DURATION:P15DT5H0M20S     DURATION:P7W      URL;CN=John
     Smith:http://example.com/urivalue.html  X-SKI-TITLE;RSVP=TRUE:  This  is an
     extension            property             SUMMARY:"No             Property"
     SUMMARY;RSVP=TRUE;RSVP=FALSE:Calendaring  Interoperability Planning Meeting
     SUMMARY;ALTREP=This is  an  xname:altrep  SUMMARY;CUTYPE=DESCRIPTION  is  a
     keyword:Xname      parameter     DTEND:19990605     DTSTART:19990605T103012
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