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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def set_value(self, arr, key, value):
 """ Fast lookup of value from 1-dimensional ndarray. Notes ----- Only use this if you know what you're doing. """

        self._engine.set_value(com.values_from_object(arr),
                               com.values_from_object(key), value)