What is the purpose of the __str__ and __repr__ methods in Python classes, and how do they differ in their use cases?

Q6: What is the purpose of the __str__ and __repr__ methods in Python classes, and how do they differ in their use cases?

A6:

• __str__ Method:

  • The __str__ method is responsible for returning a human-readable string representation of an object.
  • It is invoked when the str() function is used on an object or when the print() function is called with the object as an argument.
  • This method is typically used for displaying information to end-users in a readable format.

  python
  class MyClass:
      def __str__(self):
          return "This is an instance of MyClass."
  
  obj = MyClass()
  print(str(obj))  # Output: This is an instance of MyClass.
  

• __repr__ Method:

  • The __repr__ method is responsible for returning an unambiguous string representation of an object, primarily for debugging purposes.
  • It is invoked when the repr() function is used on an object or when the backtick notation (``) is used in Python 2 (Note: backticks are not used for repr in Python 3).
  • This method is used by developers to obtain detailed information about an object.

  python
  class MyClass:
      def __repr__(self):
          return "MyClass()"
  
  obj = MyClass()
  print(repr(obj))  # Output: MyClass()
  

In summary, __str__ is for creating a readable representation of an object for end-users, while __repr__ is intended for developers to obtain an unambiguous and detailed representation of an object for debugging and development purposes.