docs: def getSCDPURL(self, serviceType, default=None):
          """Returns the SCDP (Service Control Protocol Document) URL for a given service type.
  
          When the device definitions have been loaded with :meth:`~simpletr64.DeviceTR64.loadDeviceDefinitions` this
          method returns for a given service type/namespace the associated URL to the SCDP. If the device definitions
          have not been loaded a default value can be given which gets returned instead. The SCDP specifies all the
          interaction functionality a device provides.
  
          :param serviceType: the service type to look up for
          :param default: the default return value in case the service type is not found and device definitions are not
              loaded
          :type default: str or None
          :return: the URL/URI
          :rtype: str or None
          :raises ValueError: if the device did load device definitions and the service type is not known.
  
          .. seealso::
  
              :meth:`~simpletr64.DeviceTR64.loadDeviceDefinitions`
          """
          if serviceType in self.__deviceServiceDefinitions.keys():
              return self.__deviceServiceDefinitions[serviceType]["scpdURL"]
  
          # check if definitions have been loaded, then dont return the default
          if self.__deviceXMLInitialized:
              raise ValueError("Device do not support given serviceType: " + serviceType)
  
          return default