Python3基础 dict __len__ 统计键值对的数量

 

•        Python : 3.7.3
•          OS : Ubuntu 18.04.2 LTS
•         IDE : pycharm-community-2019.1.3
•       Conda : 4.7.5
•    typesetting : Markdown

 

code

coder@ubuntu:~$ source activate py37
(py37) coder@ubuntu:~$ ipython
Python 3.7.3 (default, Mar 27 2019, 22:11:17)
Type 'copyright', 'credits' or 'license' for more information
IPython 7.5.0 -- An enhanced Interactive Python. Type '?' for help.

In [1]: my_dict = {
   ...:     "子": "鼠",
   ...:     "丑": "牛",
   ...:     "寅": "虎",
   ...:     "卯": "兔",
   ...:     "辰": "龙",
   ...:     "巳": "蛇",
   ...:     "午": "马",
   ...:     "未": "羊",
   ...:     "申": "猴",
   ...:     "酉": "鸡",
   ...:     "戌": "狗",
   ...:     "亥": "猪"
   ...: }                                                                       

In [2]: my_dict.__len__()
Out[2]: 12

In [3]: exit
(py37) coder@ubuntu:~$ conda deactivate
coder@ubuntu:~$ 

 

source_code

def __len__(self, *args, **kwargs): # real signature unknown
    """ Return len(self). """
    pass

 

resource

• [文档 - English] docs.python.org/3
• [文档 - 中文] docs.python.org/zh-cn/3
• [规范] www.python.org/dev/peps/pep-0008
• [规范] zh-google-styleguide.readthedocs.io/en/latest/google-python-styleguide/python_language_rules
• [源码] www.python.org/downloads/source
• [ PEP ] www.python.org/dev/peps
• [平台] www.cnblogs.com
• [平台] gitee.com

 

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