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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 recursive_update(self, k, d):
 """Recursively update a top-level option in the run control Parameters k : string the top-level key d : dictionary or similar the dictionary to use for updating """

        u = self.__getitem__(k)
        self.store[k] = _recursive_update(u, d)