def __init__( self, sites ):
        """
        Initialise an Cluster instance.

        Args:
            sites (List(Site): The list of sites that make up the cluster.

        Returns:
            None
        """
        self.sites = set( sites )
        self.neighbours = set()
        for s in self.sites:
            self.neighbours.update( s.p_neighbours ) 
        self.neighbours = self.neighbours.difference( self.sites )
def __init__ ( self , sites ) : self . sites = set ( sites ) self . neighbours = set ( ) for s in self . sites : self . neighbours . update ( s . p_neighbours ) self . neighbours = self . neighbours . difference ( self . sites )
Initialise an Cluster instance.

        Args:
            sites (List(Site): The list of sites that make up the cluster.

        Returns:
            None