Python3基礎 list dict set 均為unhashable type

 

•        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]: hash(list())                                                            
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-1-3e2eb619e4e4> in <module>
----> 1 hash(list())

TypeError: unhashable type: 'list'

In [2]: hash(dict())                                                            
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-2-7762fff637c6> in <module>
----> 1 hash(dict())

TypeError: unhashable type: 'dict'

In [3]: hash(set())                                                             
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-3-2699417ebeac> in <module>
----> 1 hash(set())

TypeError: unhashable type: 'set'

In [4]: exit                                                                    
(py37) coder@ubuntu:~$ conda deactivate
coder@ubuntu:~$ 

 

source_code

def hash(*args, **kwargs): # real signature unknown
    """
    Return the hash value for the given object.
    
    Two objects that compare equal must also have the same hash value, but the
    reverse is not necessarily true.
    """
    pass

 

reference

• https://blog.csdn.net/u013939918/article/details/78032046
• https://www.jianshu.com/p/49f940b2c03e
• https://blog.csdn.net/weixin_37641832/article/details/84332763

 

resource

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

 

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Python具有開源、跨平台、解釋型、交互式等特性，值得學習。
Python的設計哲學：優雅，明確，簡單。提倡用一種方法，最好是只有一種方法來做一件事。
代碼的書寫要遵守規范，這樣有助於溝通和理解。
每種語言都有獨特的思想，初學者需要轉變思維、踏實踐行、堅持積累。