new_contents: 
  class SdpGeneric(str):
      def getCopy(self):
          return self
  
subject: Rewrite SDP body parser. By definition in the RFC4566, the SDP body has very simple fixed syntax, so that complexity of our internal representation modelled after more complex SIP objects is not justifyed. This brings up to 20-25% speed increase on parse/__str__() operations, but what also important makes using the SDP classes easier and allows us to implement more features easily, which otherwise would be too complex to do penalizing execution time.