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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 runJob(self, rdd, partitionFunc, partitions=None, allowLocal=False):
 """ Executes the given partitionFunc on the specified set of partitions, returning the result as an array of elements. If 'partitions' is not specified, this will run over all partitions. [0, 1, 4, 9, 16, 25] [0, 1, 16, 25] """

        if partitions is None:
            partitions = range(rdd._jrdd.partitions().size())

        # Implementation note: This is implemented as a mapPartitions followed
        # by runJob() in order to avoid having to pass a Python lambda into
        # SparkContext#runJob.
        mappedRDD = rdd.mapPartitions(partitionFunc)
        sock_info = self._jvm.PythonRDD.runJob(self._jsc.sc(), mappedRDD._jrdd, partitions)
        return list(_load_from_socket(sock_info, mappedRDD._jrdd_deserializer))