func_code: def swap_unique_keys_values(d):
      dic = {}
      values = []
      notunique = []
      for key in d:
          if d[key] in values:
              notunique.append(d[key])
          else:
              values.append(d[key])
      for key in d:
          if not d[key] in notunique:
              dic[d[key]] = key
      return dic