Inheriting Properties from Built-in classes

• In Python, you can inherit properties and methods from built-in classes by using inheritance. Built-in classes in Python, such as list, dict, str, etc., provide a rich set of functionalities that can be extended or customized through inheritance.

Inheriting from list

• Let's say you want to create a custom list class that adds some additional functionality to a standard list : Refer q1.py

• super() function returns a proxy object that represents the parent class of the current instance. It allows you to call methods of the superclass from within a subclass.

Refer q3.py

• __setitem__() is a special method used for assignment to an index in an object. It is invoked when you use square brackets ([]) to assign a value to an index in an object, typically in sequence-like objects such as lists, dictionaries, or custom classes that implement this method.

Inheriting from dict

• Similarly, you can inherit from the dict class to create a custom dictionary with additional functionalities : Refer q2.py

• list() function :

  • list() is a built-in function used to create a new object in python.
  • When you pass an iterable (like a tuple, set, dictionary keys, etc.) to list(), it converts it into a new list object containing all elements of that iterable.
  • If list() is called without arguments, it returns an empty list.

• keys() method:

  • In Python, keys() is a method available on dictionary objects (dict type) that returns a view object representing the keys of the dictionary.

Refer q4.py

• The getitem() method :

  • in Python is a special method, also known as a magic method or dunder method, which allows an object to be accessed using the square bracket notation ([]). This method is automatically called when you use square brackets to access an item from an object, such as a list, dictionary, or a custom object that implements __getitem__().

  • __getitem__() allows objects to support indexing and slicing operations. It defines what happens when you use obj[key] to retrieve an item from obj.

  class CustomList:
      def __init__(self, data):
          self.data = data
      
      def __getitem__(self, index):
          return self.data[index]
  
  # Creating an instance of CustomList
  my_list = CustomList([1, 2, 3, 4, 5])
  
  # Accessing elements using square brackets
  print(my_list[0])  # Output: 1
  print(my_list[2])  # Output: 3
  
  # Iterating over the CustomList
  for item in my_list:
      print(item)  # Output: 1, 2, 3, 4, 5