Interview Q&A / Python

1. How do you create and raise a custom exception in Python?

   Subclass Exception (not BaseException), give it a clear name ending in Error, and raise it with raise. Add attributes or a message in __init__ if callers need details. A shared base class lets callers catch a whole family.

   BeginnerQuick answer1 min read
2. What is the difference between __str__ and __repr__ in Python?

   __str__ gives a readable description meant for users and is used by print() and str(). __repr__ gives an unambiguous description meant for developers, ideally looking like code that recreates the object. If only __repr__ exists, print falls back to it.

   BeginnerQuick answer1 min read
3. What is the difference between type() and isinstance() in Python?

   type(x) returns the exact class of x, so comparing with == ignores inheritance. isinstance(x, C) is True if x is an instance of C or of any subclass of C, so it is the usual choice for type checks.

   BeginnerQuick answer1 min read