code: def registerRti(self, fullName, fullClassName, extensions=None, pythonPath=''):
          
          check_is_a_sequence(extensions)
          extensions = extensions if extensions is not None else []
          extensions = [prepend_point_to_extension(ext) for ext in extensions]
  
          regRti = RtiRegItem(fullName, fullClassName, extensions, pythonPath=pythonPath)
          self.registerItem(regRti)
docs: Class that maintains the collection of registered inspector classes.
              Maintains a lit of file extensions that open the RTI by default.