code: def symmetries(self):
          
  
          symmetry_cycles = set([])
          symmetries = set([])
          for match in GraphSearch(EqualPattern(self))(self):
              match.cycles = match.get_closed_cycles()
              if match.cycles in symmetry_cycles:
                  raise RuntimeError("Duplicates in EqualMatch")
              symmetry_cycles.add(match.cycles)
              symmetries.add(match)
          return symmetries
docs: Graph symmetries (permutations) that map the graph onto itself.