Here are a few question-based titles, tailored to your provided article content: Option 1 (Focus on Distinction): * How Does Python Differentiate Between Class Variables and Instance Variables? Opt

Understanding Python Class and Instance Variables

In Python, objects created from a class can possess two types of variables: class variables and instance variables. Class variables are shared among all instances of a class, while instance variables are unique to each instance.

Class Variables

Class variables are defined outside of the __init__ method. They are declared using the class name, followed by a dot and the variable name. For example:

<code class="python">class MyClass:
    class_variable = 100</code>

All instances of MyClass will have access to the class_variable.

Instance Variables

Instance variables are defined within the __init__ method. They are declared using the self keyword, followed by the variable name. For example:

<code class="python">class MyClass:
    def __init__(self):
        self.instance_variable = 200</code>

Each instance of MyClass will have its own unique instance_variable.

Example Clarification

Regarding the example mentioned in the question:

• In the first example, list is defined as a class variable outside of the __init__ method. Therefore, it is shared among all instances of testClass. When you call p.list and f.list, you are accessing the same class variable.
• In the second example, list is defined within the __init__ method. Therefore, it is an instance variable. When you call p.list and f.list, you are accessing different instance variables, each with its own thing appended.

Advanced Example

The following example demonstrates a more complex scenario:

<code class="python">class MyClass:
    class_variable = ['foo']
    
    def __init__(self):
        self.instance_variable = ['bar']</code>

In this example, class_variable is a class variable and instance_variable is an instance variable. When you access x.list, you are accessing the instance variable, which has been modified to contain 'thing'. When you access testClass.list, you are accessing the class variable, which remains unmodified.

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