09 Classes Advanced

Question 1

What are some of the special methods every class inherits from the base class “object”?

Answer 1

• __eq__(self, other)
• __hash__(self)
• __str__(self)
• __lt__(self, other)
• ..

Question 2

In Python, what does it mean to “override” a method?

Answer 2

It means I change the behavior of the method in a subclass. When calling the method from an object of this subclass, the behavior is different than when calling the method from an object of the superclass.

Question 3

In Python, what is operator overloading?

Answer 3

It means the behavior of an operator (e.g. ==) is changed for a class.

Question 4

There are some operators that have no default support. What are some we have learned about and how can we provide support for them?

Answer 4

• • : __add__(self, other)
• • : __mul__(self, other)
• [] : __getitem__(self, key)
• in: __contains__(self, item)

Question 5

There are some features that have no default support. What are some we have learned about and how can we provide support for them?

Answer 5

• Iteration: __iter__(self)
• Making objects callable: __call__(self, .. )
• Context managers (in combination with with-statement): __enter__(self) and __exit__(self, exc_type, exc_value, traceback)