def METHOD_NAME(self):
    n = Power(None)
    class _config:
        options = {"country": None, "language": None}
    class father:
        config = _config()
    n.father = father()
    n.init(None)
    data = {'id': 0, 'lat': 0, 'lon': 0}
    self.check_not_err(n.node(data, {'frequency': '50', 'power': 'transformer'}), expected={'class': 91003, 'subclass': 0})
    self.check_err(n.node(data, {'power': 'transformer'}), expected={'class': 91003, 'subclass': 0})