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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 remove_sites_from_neighbours( self, remove_labels ):
 """ Removes sites from the set of neighbouring sites if these have labels in remove_labels. Args: Remove_labels (List) or (Str):
 List of Site labels to be removed from the cluster neighbour set. Returns: None """

        if type( remove_labels ) is str:
            remove_labels = [ remove_labels ]
        self.neighbours = set( n for n in self.neighbours if n.label not in remove_labels )