Python interview Question and Answers
Python is a high-level, general-purpose, and dynamically typed programming language. It was created by Guido van Rossum and first released in 1991. Python has gained widespread popularity due to its simplicity, readability, and versatility. Below are some of the best Python Interview Question and Answers.
1) What is Python, and why is it popular?
ANS : Python is a high-level, interpreted programming language known for its simplicity and readability. It’s popular because of its ease of use, extensive standard library, and a large and active community of developers.
2) What are the key differences between Python 2 and Python 3?
ANS : Python 3 is the latest version and has several key differences from Python 2, including changes in print statement, division, Unicode support, and various library updates. It’s recommended to use Python 3 for new projects.
3) Explain Python’s Global Interpreter Lock (GIL).
ANS : GIL is a mutex that allows only one thread to execute in a Python process at a time. It can limit the utilization of multi-core processors in multi-threaded Python programs.
4) How do you comment in Python?
ANS : You can use the ‘#’ character for single-line comments, and triple-quotes (”’ or “””) for multi-line comments.
5) What are the different data types in Python?
ANS : Common data types include int, float, str, list, tuple, dictionary, and set. Python also has more specialized data types like bool, complex, and bytes.
6) Explain the difference between list and tuple in Python.
ANS : Lists are mutable, while tuples are immutable. This means you can modify a list after creation, but not a tuple. Lists are defined with square brackets, and tuples with parentheses.
7) What is a Python dictionary, and how is it different from a list?
ANS : A dictionary is an unordered collection of key-value pairs. Unlike lists, which are indexed by a range of numbers, dictionaries are indexed by keys. They are created using curly braces and colons: {‘key’: ‘value’}.
8) Explain the use of the if name == “main“: statement.
ANS : It’s a common idiom used to check whether a Python script is being run as the main program or if it is being imported as a module into another script. Code within this block will only execute if the script is the main program.
9) How do you open and close files in Python?
ANS : You can open a file using the open() function and close it using the close() method. It’s important to close files to free up system resources. Alternatively, you can use a with statement to automatically close the file when done.
10) What is a decorator in Python?
ANS : A decorator is a function that wraps another function to modify its behavior. Decorators are often used to add functionality to functions or methods without changing their code.
11) Explain the difference between deep copy and shallow copy of a list.
ANS : A shallow copy creates a new list but references the same objects as the original list. A deep copy creates a completely independent copy with its own objects. You can use copy.copy() for a shallow copy and copy.deepcopy() for a deep copy.
12) What is a lambda function in Python?
ANS : A lambda function is a small, anonymous function defined with the lambda keyword. They are often used for short, simple operations and can take any number of arguments but can only have one expression.
These are some common Python interview questions. Be prepared to discuss these topics and demonstrate your knowledge of Python during an interview. The depth of the questions may vary depending on the position and the level of expertise required.