func_code: def swap_unique_keys_values(d):
      for w in list(d.items()):
          m = ''
          if list(d.items()).count(w) > 1:
              m = w
              d.popitem(d[w])
          d.popitem(d[m])
      d = {v: k for k, v in list(d.items())}
      return d