code: def purge_stream(self, stream_id, remove_definition=False, sandbox=None):
          
  
          if sandbox is not None:
              raise NotImplementedError
  
          if stream_id not in self.streams:
              raise StreamNotFoundError(stream_id)
  
          self.data[stream_id] = StreamInstanceCollection()
          self.streams[stream_id].calculated_intervals = TimeIntervals()
  
          if remove_definition:
              del self.data[stream_id]
              del self.streams[stream_id]
docs: Clears all the data in a given stream and the calculated intervals
          
          :param stream_id: The stream id
          :param remove_definition: Whether to remove the stream definition as well
          :param sandbox: The sandbox id
          :return: None