Part - 1 Python interview questions and answers

What are the key features of Python?

Some key features of Python include its support for object-oriented, imperative, and functional programming styles, as well as its built-in data structures and dynamic typing. It also has a large standard library that supports many common programming tasks.

How does Python handle memory management?

Python uses a private heap space to manage its memory. The Python memory manager is responsible for allocating and deallocating memory for Python objects. It also manages a private heap space that is used by the interpreter to store objects. Python's garbage collector reclaims memory by freeing unreferenced objects.

Can you explain the difference between a tuple and a list in Python?

Both tuples and lists are used to store a collection of items in Python, but they have some key differences. A tuple is an immutable data structure, meaning its elements cannot be changed or modified once it is created. A list, on the other hand, is a mutable data structure, which means its elements can be modified after it is created. Tuples are also generally faster and use less memory than lists.

What are the benefits of using a Python dictionary?

Python dictionaries are a built-in data structure that allows you to store key-value pairs. They are very efficient for looking up values by key and are also very flexible, allowing you to store a wide range of data types. Dictionaries also have several built-in methods for performing common operations like sorting, merging, and updating.

What is a decorator in Python?

A decorator is a design pattern in Python that allows you to add new functionality to an existing function or class without modifying its code. Decorators are implemented using special functions or classes that take a function or class as an argument and return a new function or class with the desired behavior. They are often used to add logging, caching, or other functionality to existing code.

How can you make a Python script executable on Unix?

To make a Python script executable on Unix, you need to add the following line to the top of the script: #!/usr/bin/env python. Then, you need to make the script executable by running the command chmod +x script.py. Finally, you can run the script by calling ./script.py on the command line.

Explain the use of *args and **kwargs in python?

The *args and **kwargs in Python are used to pass a variable number of arguments to a function. *args is used to pass a non-keyworded variable-length argument list, while **kwargs is used to pass a keyworded variable-length argument list. These can be used to write more flexible code, and to handle functions with a variable number of argument.

What is the difference between shallow and deep copy in Python?

A shallow copy creates a new object with a reference to the original object, while a deep copy creates a new object with a completely independent copy of the original object. In the case of shallow copy if we modify the original object, the copy will also be modified, whereas in the case of deep copy, the copy remains unchanged if the original object is modified.

How do you perform exception handling in Python?

In Python, exception handling is done using the try-except block. The try block contains the code that may raise an exception, and the except block contains the code that will be executed if an exception is raised. You can also use the finally block to execute code that must be run regardless of whether an exception is raised or not.

How do you check if a variable is an instance of a particular class in Python?

In Python, you can use the isinstance() function to check if a variable is an instance of a particular class. The function takes two arguments, the variable to check and the class to check against, and returns True if the variable is an instance of the class, and False otherwise.

Example: isinstance(var, class)

How do you define a class in Python?

In Python, a class is defined using the class keyword, followed by the name of the class, and a colon. The class definition includes a constructor method, which is defined using the init() method. The class definition can also include other methods and properties that define the behavior of the class.

How do you create an object from a class in Python?

In Python, you can create an object from a class by calling the class name as a function and passing any required arguments to the constructor. The object is then initialized with the values passed to the constructor, and can be used to access the methods and properties defined in the class.