docs: def offsets(self, group=None):
          """Get internal consumer offset values
  
          Keyword Arguments:
              group: Either "fetch", "commit", "task_done", or "highwater".
                  If no group specified, returns all groups.
  
          Returns:
              A copy of internal offsets struct
          """
          if not group:
              return {
                  'fetch': self.offsets('fetch'),
                  'commit': self.offsets('commit'),
                  'task_done': self.offsets('task_done'),
                  'highwater': self.offsets('highwater')
              }
          else:
              return dict(deepcopy(getattr(self._offsets, group)))