code: def _remove_empty_output(self):
          
          output = []
          for key in self.output_dict:
              if self.output_dict[key] is not None and 'full_text' in self.output_dict[key]:
                  output.append(self.output_dict[key])
          return output
docs: If plugins haven't been initialised and therefore not sending output or
          their output is None, there is no reason to take up extra room on the
          bar.