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dir, __dict__ and help method in Python

 


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dir, __dict__, and help Method in Python

Python provides several built-in functions and attributes that are useful for introspection and understanding objects and their attributes. Three such tools are dir(), __dict__, and help().

1. dir()

The dir() function returns a list of the attributes and methods of an object. It can be used on any object to see its properties.


# Using dir() on a list
example_list = [1, 2, 3]
print(dir(example_list))

Output: ['__add__', '__class__', '__contains__', ... , 'append', 'clear', 'copy', ...]

2. __dict__

The __dict__ attribute is a dictionary representation of an object's attributes. It shows the object's attributes and their values.


# Define a simple class
class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

# Create an instance of the class
person = Person('John', 30)
print(person.__dict__)

Output: {'name': 'John', 'age': 30}

3. help()

The help() function is used to display the documentation of modules, functions, classes, and methods. It provides a quick way to get information about Python objects.


# Using help() on a list
help(example_list)

Output: (Displays the documentation and available methods of the list object)

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