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