Python interview questions and answers

A wrapper calls the original and adds behavior

login_required checks request.user.is_authenticated and redirects or returns 403 depending on configuration.

A list comprehension builds the whole list in memory immediately.

send(value) resumes the generator and makes yield return that value inside the function.

You can yield lines or parsed chunks instead of reading the file into one string or list.

yield from subgen delegates iteration to another iterable or generator, forwarding values, send, and throw.

MRO is the linear order Python uses to find attributes on a class and its bases.

A diamond occurs when two bases share a common ancestor, so a method could be inherited twice.

ABCs, from abc.ABC, let you declare abstract methods that subclasses must implement.

@property turns a method into managed attribute access so callers use obj.x instead of obj.x().

Use inheritance for true is-a relationships and shared polymorphic APIs.

The venv interpreter's sys.prefix points at the env directory, so imports look in venv/lib/site-packages first.

venv ships with Python 3 and is enough for most Django apps.

Editable install links the project into site-packages so code changes apply without reinstalling.

Specifiers such as >=, ~=, and == constrain acceptable versions on a requirement line.

The WSGI/ASGI handler loads middleware, resolves the URL, and calls the view.

Function-based views are clearer for one-off endpoints with simple branching.

A context processor is a function that receives the request and returns a dict merged into every template context.

A child template starts with {% extends 'base.html' %} and fills named {% block %} regions.

select_related performs a SQL join for forward ForeignKey and OneToOne relations and is a single query.