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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 reduceByKeyLocally(self, func):
 """ Merge the values for each key using an associative and commutative reduce function, but return the results immediately to the master as a dictionary. This will also perform the merging locally on each mapper before sending results to a reducer, similarly to a "combiner" in MapReduce. [('a', 2), ('b', 1)] """

        func = fail_on_stopiteration(func)

        def reducePartition(iterator):
            m = {}
            for k, v in iterator:
                m[k] = func(m[k], v) if k in m else v
            yield m

        def mergeMaps(m1, m2):
            for k, v in m2.items():
                m1[k] = func(m1[k], v) if k in m1 else v
            return m1
        return self.mapPartitions(reducePartition).reduce(mergeMaps)