10+ Rehlko Interview Questions and Answers

Method overloading allows multiple methods with the same name but different parameters; overriding replaces a method in a subclass.

• Method Overloading: Same method name with different parameters in the same class.

• Example: def add(self, a: int, b: int) and def add(self, a: float, b: float).

• Method Overriding: Subclass provides a specific implementation of a method already defined in its superclass.

• Example: class Animal has a method speak(), class Dog overrides it with its own sp...read more

Multithreading allows concurrent execution of tasks in Python, enhancing performance and responsiveness in applications.

• Concurrency: Multiple threads run simultaneously, improving application responsiveness.

• Thread Creation: Use the 'threading' module to create threads. Example: 'threading.Thread(target=func).start()'.

• Synchronization: Use locks (e.g., 'threading.Lock') to prevent race conditions when accessing shared resources.

• Thread Lifecycle: Threads can be in states like 'n...read more

Method Resolution Order (MRO) is the order in which classes are searched for a method or attribute in Python.

• MRO is determined by the C3 linearization algorithm in Python.

• It follows a depth-first left-to-right traversal of the class hierarchy.

• MRO is important in multiple inheritance scenarios to resolve method conflicts.

• Example: class A: pass class B(A): pass class C(A): pass class D(B, C): pass

Class method is bound to the class itself, while static method is not bound to any specific instance or class.

• Class method takes 'cls' as the first parameter, allowing access to class variables and methods.

• Static method does not take any special parameters and does not have access to class or instance variables.

• Class method can be called on both the class and instances of the class.

• Static method is mainly used for utility functions that do not require access to class or insta...read more

Transactions in SQL are a way to ensure data integrity by grouping multiple SQL statements into a single unit of work.

• Transactions help maintain the ACID properties (Atomicity, Consistency, Isolation, Durability) of a database.

• They allow multiple SQL statements to be executed as a single unit, either all succeeding or all failing.

• Transactions can be started with BEGIN TRANSACTION, COMMIT to save changes, or ROLLBACK to undo changes.

• Example: transferring money from one account...read more

DRF provides JSON, BrowsableAPI, TemplateHTML, and AdminRenderer classes for rendering responses.

• JSONRenderer: Renders data in JSON format.

• BrowsableAPIRenderer: Renders data in a browsable HTML format with forms for interacting with the API.

• TemplateHTMLRenderer: Renders data using a specified template in HTML format.

• AdminRenderer: Renders data in a format suitable for Django admin interface.

Decorators in Python are functions that modify the behavior of other functions or methods.

• Decorators are used to add functionality to existing functions without modifying their code.

• Types of decorators in Python include function decorators, class decorators, and method decorators.

• Example: @staticmethod and @classmethod are built-in decorators in Python.

List is a built-in Python data structure that can hold elements of different data types, while Array is a data structure from the NumPy library that can hold elements of the same data type.

• List is a dynamic array that can grow or shrink in size, while Array has a fixed size.

• List can hold elements of different data types, while Array can only hold elements of the same data type.

• List is a part of Python's standard library, while Array is part of the NumPy library.

• List is more f...read more

PEP 8 is the style guide for Python code, promoting readability and consistency in Python programming.

• Encourages using 4 spaces per indentation level instead of tabs.

• Recommends limiting lines to 79 characters for better readability.

• Suggests using blank lines to separate functions and classes.

• Promotes using descriptive variable names, e.g., 'user_age' instead of 'ua'.

• Advises on proper import ordering: standard libraries first, then third-party libraries, and finally local appl...read more