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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 merge( self, other_cluster ):
 """ Combine two clusters into a single cluster. Args: other_cluster (Cluster):
 The second cluster to combine. Returns: (Cluster):
 The combination of both clusters. """

        new_cluster = Cluster( self.sites | other_cluster.sites )
        new_cluster.neighbours = ( self.neighbours | other_cluster.neighbours ).difference( new_cluster.sites )
        return new_cluster