code: def uniquify(model):
      '''
      Remove all duplicate relationships
      '''
      seen = set()
      to_remove = set()
      for ix, (o, r, t, a) in model:
          hashable_link = (o, r, t) + tuple(sorted(a.items()))
          #print(hashable_link)
          if hashable_link in seen:
              to_remove.add(ix)
          seen.add(hashable_link)
  
      model.remove(to_remove)
      returf uniquify(model):
      '''
      Remove all duplicate relationships
      '''
      seen = set()
      to_remove = set()
      for ix, (o, r, t, a) in model:
          hashable_link = (o, r, t) + tuple(sorted(a.items()))
          #print(hashable_link)
          if hashable_link in seen:
              to_remove.add(ix)
          seen.add(hashable_link)
  
      model.remove(to_remove)
      return
docs: Remove all duplicate relationships