python 简化以下代码根据我的输入修改数字生成的长度 digits = 0123456789 combinations_num = for i in digits for j in digits for k in digits for l in digits combin

digits = '0123456789' combinations_num = {} for combination in itertools.product(digits, repeat=4): combinations_num[''.join(combination)] = True letters = string.ascii_lowercase combinations_str = {} for combination in itertools.product(letters, repeat=2): combinations_str[''.join(combination)] = True print(combinations_num.keys()) print(combinations_str.keys())