def kruskal(vs, es):
  f = []
  sets = [set(v) for v in vs]

  find_set = lambda v: [x for x in sets if v in x][0]

  def merge_sets_that_contains(u, v):
    setv = find_set(v)
    newsets = [x for x in sets if v not in x]
    newsets = [setv.union(x) if u in x else x for x in newsets]
    return newsets

  sorted_es = [e for e,w in sorted(es, key=lambda e: e[1])]

  for (u, v) in sorted_es:
    if find_set(u) != find_set(v):
      f += [(u, v)]
      sets = merge_sets_that_contains(u,v)

  return f

if __name__ == '__main__':
  vs = [chr(i) for i in range(ord('a'), ord('h') + 1)]
  es = [
    (('a', 'b'), 1),
    (('b', 'c'), 5),
    (('c', 'd'), 3),
    (('d', 'a'), 7),
  
    (('e', 'f'), 2),
    (('f', 'g'), 6),
    (('g', 'h'), 8),
    (('h', 'e'), 4),
  
    (('b', 'f'), 10),
    (('c', 'e'), 9),
    (('d', 'h'), 11)
  ]

  print(kruskal(vs,es))