code: def backup(self, paths=None):
          
          if not paths:
              paths = self._get_paths()
  
          try:
              self._backup_compresslevel(paths)
          except TypeError:
              try:
                  self._backup_pb_gui(paths)
              except ImportError:
                  self._backup_pb_tqdm(paths)
  
          # Delete source if specified
          if self.delete_source:
              shutil.rmtree(self.source)
          return self.zip_filename
docs: Backup method driver.