class Define class
Last updated: 2026-09-22
class Define class
class defines a new type; supports single and multiple inheritance.
| Category | Keywords & Statements |
|---|---|
| Kind | Keyword / Statement |
| Python Version | all |
📝 Syntax
class Name(Base1, Base2, ...):
body▶ Example
Edit the code, press Run, and see the result in the output panel:
Output：
woof🏷️ Related Keywords / Statements
💡 Related Cases
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❓ FAQ
QWhy must the first parameter of a method be `self`?
A`self` refers to the current instance. When you call an instance method, Python passes the instance in as the first argument automatically. Omitting `self` causes a «missing 1 required positional argument» error.
QIs `__init__` a constructor?
AStrictly speaking it is an instance-initialization method: it is called after the object is created to set up its initial state (`self.x = ...`). The method actually responsible for allocating memory and creating the object is `__new__`.
QWhat is the difference between class attributes and instance attributes?
AAttributes defined in the class body and accessed via the class name or an instance are class attributes, shared by all instances. Attributes assigned inside `__init__` with `self.x =` are instance attributes, independent per instance. When names collide, the instance attribute shadows the class attribute.
