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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 partition(self):
 """Convenience function for accessing the first partition in the partitions list, when there is only one."""


        if not self.partitions:
            return None

        if len(self.partitions) > 1:
            raise ValueError(
                "Can't use this method when there is more than one partition")

        return list(self.partitions.values())[0]