def _reroot(self):
        '''Run the re-rooting algorithm in the Rerooter class.'''
        rerooter = Rerooter()
        self.tree = rerooter.reroot_by_tree(self.reference_tree, 
                                                self.tree)
def _reroot ( self ) : rerooter = Rerooter ( ) self . tree = rerooter . reroot_by_tree ( self . reference_tree , self . tree )
Run the re-rooting algorithm in the Rerooter class.