def __getitem__(self, rule):
        """Return the existing version of the classifier rule having the
        same condition and action and appearing in this action set. This
        is useful for looking up a rule to avoid duplication."""
        assert rule.action is self._action
        return self._rules[rule.condition]
def __getitem__ ( self , rule ) : assert rule . action is self . _action return self . _rules [ rule . condition ]
Return the existing version of the classifier rule having the
        same condition and action and appearing in this action set. This
        is useful for looking up a rule to avoid duplication.