docs: def create_stream(self, stream_id, sandbox=None):
          """
          Create the stream
          
          :param stream_id: The stream identifier
          :param sandbox: The sandbox for this stream
          :return: None
          :raises: NotImplementedError
          """
          if sandbox is not None:
              raise NotImplementedError
  
          logging.debug("Creating asset stream {}".format(stream_id))
  
          if stream_id in self.streams:
              raise StreamAlreadyExistsError("Stream with id '{}' already exists".format(stream_id))
  
          stream = AssetStream(channel=self, stream_id=stream_id, calculated_intervals=None,
                               last_accessed=utcnow(), last_updated=utcnow(), sandbox=sandbox)
          self.streams[stream_id] = stream
          return stream