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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 get_partition_id(self, key):
 """ Returns the partition id for a Data key. :param key: (object), the data key. :return: (int), the partition id. """

        data = self._client.serialization_service.to_data(key)
        count = self.get_partition_count()
        if count <= 0:
            return 0
        return hash_to_index(data.get_partition_hash(), count)