text: def balanced(str):
      open_bracket = "["
      close_bracket = "]"
      stack = []
      for i in str:
          if i == open_bracket:
              stack.append(i)
          elif i == close_bracket:
              if len(stack) > 0:
                  stack.pop()
              else:
                  return "no están"
      if len(stack) == 0:
          return "están"
      else:
          return "no están"
  