code: def generate_instance(self, timestamp, value, meta_data):
          
          if not self.filters or meta_data in self.filters:
              if self.filters:
                  logging.debug('Filtered in  for {} from {}'.format(meta_data, self.filters))
              return StreamMetaInstance(StreamInstance(timestamp=timestamp, value=value), meta_data)
          if self.filters:
              logging.debug('Filtered out for {} from {}'.format(meta_data, self.filters))
          return None
docs: Generate a stream instance, checking if the filters are matched
          :param timestamp: The timestamp
          :param value: The value
          :param meta_data: The meta data
          :return: The stream instance (or None)