code: def reset_handler(self, cmd):
          
          if cmd.from_ is None:
              # We pass through resets that init a branch because we have to
              # assume the branch might be interesting.
              self.keep = True
          else:
              # Keep resets if they indirectly reference something we kept
              cmd.from_ = self._find_interesting_from(cmd.from_)
              self.keep = cmd.from_ is not None
docs: Process a ResetCommand.