Built-in class attributes

 Built-in class attributes

In Python, there are several built-in class attributes that provide information about the class and its instances. These attributes can be accessed using the dot notation. Here are some commonly used built-in class attributes:

### `__doc__`

This attribute contains the docstring, which is a string that provides documentation for the class. It is created by placing a string literal as the first statement in the class definition.

```python

class MyClass:

    """This is a docstring."""

    pass

print(MyClass.__doc__)  # Output: This is a docstring.

```

### `__name__`

This attribute contains the name of the class as a string.

```python

class MyClass:

    pass

print(MyClass.__name__)  # Output: MyClass

```

### `__module__`

This attribute contains the name of the module in which the class is defined.

```python

# Module: mymodule.py

class MyClass:

    pass

print(MyClass.__module__)  # Output: mymodule

```

### `__bases__`

This attribute contains a tuple of the base classes of the class.

```python

class Parent:

    pass

class Child(Parent):

    pass

print(Child.__bases__)  # Output: (<class '__main__.Parent'>,)

```

### `__dict__`

This attribute contains a dictionary containing the namespace of the class, i.e., the mapping of attribute names to their values.

```python

class MyClass:

    attribute = 42

print(MyClass.__dict__)  # Output: {'__module__': '__main__', 'attribute': 42, ...}

```

### `__class__`

This attribute is an instance's class. It is equivalent to accessing the class through the instance.

```python

class MyClass:

    pass

obj = MyClass()

print(obj.__class__)  # Output: <class '__main__.MyClass'>

```

These built-in class attributes provide introspection capabilities, allowing you to inspect and retrieve information about classes and their instances at runtime. They are particularly useful for debugging, documentation, and metaprogramming.