Gets the SelfLink/ID based link of the collection node that maps to the partition key
        based on the hashing algorithm used for finding the node in the ring.

        :param str partition_key:
            The partition key to be used for finding the node in the ring.

        :return:
            The name of the collection mapped to that partition.
        :rtype: str

def GetCollectionNode(self, partition_key):
        """Gets the SelfLink/ID based link of the collection node that maps to the partition key
        based on the hashing algorithm used for finding the node in the ring.

        :param str partition_key:
            The partition key to be used for finding the node in the ring.

        :return:
            The name of the collection mapped to that partition.
        :rtype: str

        """
        if partition_key is None:
            raise ValueError("partition_key is None or empty.")

        partition_number = self._FindPartition(self._GetBytes(partition_key))
        return self.partitions[partition_number].GetNode()