(self, force=False)
Save a backup of this Flow, which can be reverted to using a
            call to .revert().
Save a backup of this Flow, which can be reverted to using a
            call to .revert().
Save a backup of this Flow which can be reverted to using a call to . revert () .
def backup(self, force=False):
        """
            Save a backup of this Flow, which can be reverted to using a
            call to .revert().
        """
        if not self._backup:
            self._backup = self._get_state()
def backup ( self , force = False ) : if not self . _backup : self . _backup = self . _get_state ( )