>>> dictionary = { 1: 'one', 2:'two', 3:'three' } >>> dictionary['ONE'] = dictionary.pop(1) >>> dictionary {2: 'two', 3: 'three', 'ONE': 'one'} >>> dictionary['ONE'] = dictionary.pop(1) Traceback (most recent call last): File "<input>", line 1, in <module> KeyError: 1
a_dict[new_key] = a_dict.pop(old_key)