Cognizant Python Developer Interview Questions and Answers

Tuple is immutable and ordered while list is mutable and ordered.

• Tuple uses () while list uses []

• Tuple is faster than list for accessing elements

• Tuple can be used as keys in dictionaries while list cannot

• Tuple can be used in string formatting while list cannot

One recursion problem is to find the factorial of a number.

• The base case is when the number is 0 or 1.

• The recursive case is to multiply the number with the factorial of (number-1).

• Example: factorial(5) = 5 * factorial(4) = 5 * 4 * factorial(3) = ... = 5 * 4 * 3 * 2 * 1 = 120.

Python is used in reality due to its simplicity, versatility, and wide range of applications.

• Python is easy to learn and read, making it a popular choice for beginners.

• It has a large standard library and many third-party modules, allowing for rapid development.

• Python is used in web development, data analysis, machine learning, scientific computing, and more.

• It is cross-platform and can run on various operating sys...read more

Yes, init method is a special method in Python classes used to initialize objects.

• The init method is called automatically when an object is created from a class.

• It is used to set initial values for object attributes.

• The init method always takes the 'self' parameter as the first argument.

• Example: def __init__(self, name, age): self.name = name; self.age = age

• The init method can also be used to perform any other set...read more

Pickling is a way to serialize Python objects, while non-pickling refers to objects that cannot be pickled.

• Pickling is used to convert Python objects into a byte stream that can be stored or transmitted.

• Non-pickling objects are those that cannot be serialized using the pickle module.

• Examples of non-pickling objects include file objects, network sockets, and database connections.

• To make an object picklable, it must...read more

Inheritance is a way to create a new class by inheriting properties and methods from an existing class.

• It allows code reusability and saves time.

• Types of inheritance are single, multiple, multilevel, and hierarchical.

• Single inheritance involves inheriting properties and methods from a single parent class.

• Multiple inheritance involves inheriting properties and methods from multiple parent classes.

• Multilevel inherit...read more