Function to get input strings for tree_collection
        tree_collection needs distvar, genome_map and labels -
        these are returned in the order above

def get_tree_collection_strings(self, scale=1, guide_tree=None):
        """ Function to get input strings for tree_collection
        tree_collection needs distvar, genome_map and labels -
        these are returned in the order above
        """
        records = [self.collection[i] for i in self.indices]
        return TreeCollectionTaskInterface().scrape_args(records)