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HomeBackend DevelopmentPython TutorialThe difference between python None and Null

The difference between python None and Null

Oct 19, 2016 pm 04:15 PM
nonenullpython

1. Python objects

To understand this, you must first understand Python objects:

Python objects have three characteristics: identity, type, and value.

Three properties are assigned when the object is created. Only the value can be changed, others are read-only.

Types themselves are also objects.

2. Null and None

is a special type of Python, Null object or None Type, it has only one value None.

It does not support any operations and does not have any built-in methods.

None and any other data Type comparisons always return False.

None has its own data type NoneType.

You can copy None to any variable, but you cannot create other NoneType objects.

>>> type(None)
<class &#39;NoneType&#39;>
>>> None == 0
False
>>> None == &#39; &#39;
False
>>> None == None
True
>>> None == False
False



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