Python Interview Questions And Answers

As of 2020, we see that there are high demand and significance for programming languages like Python. The development of applications has become easier with the help of programming languages. Python is one of the commonly used programming languages with its key features, allowing business organizations to improve efficiency and develop themselves by meeting the client requirements of the given time frames. In this article, you will learn about the different interview questions and answers which are frequently asked in Python. The frequently asked interview question and answers are curated by experts which will definitely help you to crack the interview. Let's get started.

Categories Of Python Interview Questions

Here are the frequently asked python interview questions for freshers

Q1) What do you know about Python and give a brief idea of the key features of Python?

Ans: Python is one of the programming languages that is developed to build any type of application by utilizing tools and libraries. Python is called a high-level, general-purpose, and interpreted programming language which is capable of running equally on the different type of platforms like Linux, Windows, Unix, and Macintosh. Python is a programming language that is mostly used in machine learning, data science, and artificial intelligence domains. Python is easy to learn and also requires fewer lines of code in order to develop the applications. It is specifically used for software development, scripting, web development, and mathematics.

Below is the list of features that are available in Python.

1. Interpreted: Python is referred to as an interpreter language that does not require any compilation before it is run. it is different from the other programming languages like C, C++ as they require compilation before running the application or program.

2. Dynamically typed: Python is referred to as a dynamically typed language which means that it does not require to state the type of variables during the declaration or anything like that. you are allowed to perform or declare like i=121 and then i= "I am a programmer " without getting any errors.

3. Object-oriented: Python is a language that is well suitable for object-oriented programming as it will allow the definition of the classes along with inheritance and composition.  Unlike the other programming languages, Python does not have access specifiers.

4. Functions: Functions in Python are referred to as first-class objects which can be assigned to the variables and also can be returned to the other functions and passed into the functions. The Classes are usually referred to as first-class objects.

5. Coding: Writing the code in Python is faster. However, running the same code is slower when compared to the other compiled languages. Python is capable of allowing the inclusions of C-based extensions which can help in the bottleneck Optimisation.

Q2) How is memory management performed in Python?

Ans: Python makes use of a Python memory manager to ensure that the memory management is handled efficiently. The memory will be allocated by the manager which is represented in the form of private heap space that is only possible in Python. the Python objects will be stored which are privately secured and are inaccessible to the programmer. Apart from this, Python also includes a built-in garbage collection which helps in recycling the unused memory for the private heap space.

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Q3) What do you know about Python literals?

Ans: Python literal can be referred to as the data that can be given in a constant or a variable. Python provides extensible support for the following literals.

a. String literals: String literals are referred to as those that are formed by including the text in single or double quotes.  the string literals are referred to as string values.

Example: "Kavya", "54321"

b. Numeric literals: Numeric letters are referred to as those which can be either the integer, float, or complex type.

Examples:

//Integer Literal

i=100

//Float Literal

i=100.3

//Complex literal

a=1.41b

Q4) Give a brief idea about scope in Python?

Ans: The object that is present in Python will function within a scope. A Scope is referred to as the block of code that will allow the object in Python to remain relevant. namespaces those that will help in identifying the objects that are present in the program. there will also be a scope defined for the namespaces.  Below are few examples of the script that will be created during the code execution in Python. they are:

1. Local scope: The local scope refers to the local objects that are present in the current function

2. Global scope: The Global scope refers to the objects that are available during the code execution.

3. Module level scope: The Module level scope refers to the Global objects of the current module that are accessible in the program.

4. Outermost scope: The outermost scope refers to the built-in names that are callable in the program.

Q5) What is the Lambda function in Python?

Ans: The Lambda function is referred to as an anonymous function that can have any number of parameters but only includes one statement.

Example:

i = lambda a,b ; a+b

print (i(5,6))

Q6) Give a brief idea about PEP 8 and its significance?

Ans: PEP8 refers to the Python enhancement proposal which is referred to as an official design document that includes information about the Python community, by giving the description of a new feature in Python or the different processes involved. PEP 8 is specifically significant as it is capable of documenting the style guidelines for the Python code. Apart from this it also contributes with the Python can do it and alerts you to follow these style guidelines strictly and sincerely.

Q7) Give a brief idea about Python namespaces and how they are used?

Ans: A namespace in Python is specifically used to ensure that the object names in the program are unique and can be used without any issues. The namespaces in Python are implemented as dictionaries that include the name as a key that is mapped to the corresponding object as a value. Python also allows multiple namespaces to use the same name and map it to a different separate object.  Below are a few examples of namespaces. They are:

1. Local namespace: The Local namespace includes local names that are present inside a function.  The namespace will be temporarily created for the function call and will be cleared when the function will return.

2. Global namespace: The Global namespace includes the different elements from various packages or models that are presently used in the current project.  The creation of the namespace will take place once the package is imported into the script and will end once the execution of the script is completed.

3. Built-in namespace: The built-in namespace will include the built-in functions of Python and also built-in names for the different types of exceptions.

Python Tutorial

Q8) What are Python modules? List out some of the most commonly used built-in modules in Python?

Ans: Python modules are referred to as the files that contain the Python code. The code can either include the functions, variables, or classes. A Python module is referred to as the .py file that contains executable code. some of the most commonly used built-in Python modules are:

a. os

b. sys

c. JSON

d. data time

e. random

f. math

Q9) Give a brief idea about the local variables and global variables in Python?

Ans:

Global variables: Global variables are those variables that will be declared outside the function or in the global space.

Local variables: local variables are those variables that are declared inside the function The Local variables are those variables that are declared inside the function. The local variables will be present in the local space but not in the global space like the global variables.

Example: 

i = 10

def add():

j=20

k =i + j

print(k)

add()

Output: 30

Python Technical Interview Questions

Q10) How can you capitalize the first letter of the string?

Ans: We can make use of the method called capitalize() in Python that will help you in capitalizing the first letter of the string. If the string already includes the first letter in the beginning, then it will be returning the original string.

Q11) Give a brief idea about Python functions?

Ans: A function in Python is referred to as the part of the program or the block of code that will be written once and can be used and executed any number of times in the program. A function is also referred to as the block of the self-contained statements that include the name, parameters, values, and body. Python provides the users with the flexibility to utilize the built-in functions and complete the tasks and also allows them to create of the new functions as per the user requirements. There are two different types of functions in Python. They are:

Built-in functions: Some of the built-in functions in Python include len(), count(), copy(), etc.

User-defined functions: The user-defined functions are those functions that will be created and defined by the user based on their requirements.

Basic syntax of a function in Python:

def function_name(parameters list):  

//set of statements

return a_value  

Q12) Explain the differences between the functions remove() and del statement?

Ans: The remove() function is specifically used to delete the specific object in the list. You can use the del or pop function or statement to delete the object based on the index that consists of the specific location in the list.

Q13) Does Python include a main() function?

Ans: Yes, Python includes the main() function. The main() function can be executed automatically when the Python script is run. In order to ensure to override these little things, you can use the if statement.

Q14) Briefly describe lists and tuples? Also, explain the main difference between them?

Ans: Lists and tuples in Python are referred to as the sequence data types that are capable of storing the collection of the objects in Python. The objects that are stored can have different data types. The lists are usually represented in square brackets. Example: list1 =[‘kavya’, 1, 2, 0.34]. The tuples are usually represented within parentheses. Example : tuple = (‘Kavya’, 1, 2, 0.34). The primary difference between the lists and tuples is that the lists are mutable while the tuples are immutable. The lists can be modified while the tuples will remain constant always.

Q15) What do you know about _init_?

Ans:  _init() is referred to as a constructor method in Python. This method is automatically called in order to allocate the memory as and when the new object or an instance is created. There will be an _init_ method that is associated with all the classes in Python. The _init_ method also helps in differentiating the attributes and methods that are available in the class from the local variables. Let me give you an example of it.

Class Employee:

Def _init_ (Self, fn, ln, age, salary):

self.firstname = fn

self.lastname = ln

self.age = age

self.salary = salary

//creation of a new object

Empl1 = Employee( “Kavya’, ‘Sarikonda’, 24, 120000)

Q16) Give the basic differences between .py and .pc files in Python?

Ans: .py files are those files that usually consist of the source code of the program. .pyc files are those files that usually consist of the bytecode of the program. The bytecode is obtained only after the compilation of the .py file. Also, you need to know that the .pyc files are not created for all the files that you run or work on. It will be created only for the imported files.

The Python program interpreter is responsible for checking the compiled files before the execution is performed. If the file is obtained, then the virtual machine will perform the execution. If it does not find the file, then it will check for the .py file and compiles it to the .py file, which is then executed by the Python virtual machine. The .pyc files will help in saving the execution time.

Q17) Briefly explain about iterators in Python?

Ans: An iterator is referred to as an object that remembers its state. The method called _iter_() is responsible for initializing the iterator. It also consists of a _next_() method that will return the next item in the iteration and will be pointing to the next element. An iterator is also self-iterable. Hence, in simple terms, iterators are those objects that will be iterating over the other iterable objects like lists, strings, etc.

Q18) Can you briefly explain how the concept of multi-threading is performed in Python?

Ans: Python has come up with a multi-threading package. However, if you are looking to speed up the code by multi-threading using the package, it is not recommended to do so.

Python also includes a construct called the Global Interpreter Lock called GIL. GIL is capable of allowing only one thread to be executed at one time. A GIL will be acquired by the thread and pass GIL to the next thread and it is a chain process.

This chain process takes place in a faster way, which would make the humans think that the multiple threads are being executed in parallel but, they are taking turns to get the execution done. In simple terms, if you would like to run the code faster, then the multi-threading package is not considered a good idea.

Q19) Briefly explain about PythonPATH?

Ans: PythonPATH is referred to as an environment variable that is specifically used when the module is imported. Whenever the module is imported, you will also need to lookup for the PythonPATH as it will help in checking the presence of the imported modules that are available in the different directories.

Python Interview Programming Questions

Q20) Can you explain how to break, continue and pass work in Python?

Ans:

Break: Whenever the condition is met, the break is responsible for terminating the loop, and also ensures that the control is transferred to the next statement.

Continue: Whenever the condition is met, the continue is used to ensure that some part of the loop is skipped and also ensures that the control is transferred to the beginning of the loop.

Pass: Pass is used whenever you are in need of some part of the code and would not like to perform the execution. It is usually referred to as the null operation and there will not be any changes when the pass is executed.

Q21) Can you explain what does [::-1] does?

Ans: [::-1] is used to change the order to a reverse order or reverse sequence. Let me give an example as well.

Import array as arr

Array1 = arr.array( ‘ k ’ , [10, 9, 8, 7, 6])

Array1 [::-1]

Output will be: array(‘i’, [6, 7, 8, 9, 10])

Q22) Briefly describe pickling and unpickling?

Ans: The Pickle module is capable of accepting any Python object and also convert the same into the string representation. This will be further dumped into the file using the dump function. This process is called pickling. On the other side, the process of retrieving the Python objects from the stored string representation is called unpickling.

Q23) Which function is used to convert the string into lowercase?

Ans: The lower() function is used to convert the string into lowercase. Below is an example of the same.

stg= ‘ KAVYA’

print(stg.lower())

Output: kavya

Q24) What do you understand by the term docstrings in Python?

Ans: Most of them think that comments are considered as docstrings. However, docstrings are the documentation strings that are not the comments. The docstrings are enclosed in triple quotes. The docstrings will not be assigned to any of the variables and hence also ensure that the purpose of comments is met.

Example: 

“ “ “

The code below is used for dividing 2 numbers.

“ “ “

a=10

b=2

k=a/b

Print (k)

Output: 5

Q25) What is meant by a dictionary in Python?

Ans: The dictionary in Python is the repository of the built-in datatypes. It defines the relationships that exist between the keys and values. The dictionaries consist of the keys and their corresponding values and are indexed by the keys.

Q26) What are Python libraries? List out a few of the Python libraries?

Ans: The collection of the Python packages together is called the Python library. Some of the most commonly used Python libraries are Pandas, Numpy, Scikit- learn, and many more.

Q27) How do you import the modules in Python?

Ans: The modules in Python can be imported using the import keyword. You can import the modules in three different ways.

By importing using the original module name

By using the alias name

By importing everything that is present in the array module.

Q28) List out the different types of operators supported by Python?

Ans: Python is capable of providing its extensible support to the rich set of operators to perform different operations. Below is the list of the operators supported by Python.

  • Assignment operators
  • Arithmetic operators
  • Identity operators
  • Logical operators
  • Bitwise operators
  • Membership operators

Q29) What do you understand by the term Python decorator?

Ans: The decorator is one of the most powerful and useful tools that are available in Python. This tool is used by the programmers, allowing them to modify the behavior of the class or a function. It also helps in wrapping the other function in order to extend the behavior of the function that is wrapped, without modifying it permanently.

Example:

def decoratornews():

Return another_news

Q30) Define monkey patching in Python?

Ans: Monkey patching in Python usually refers to the modifications that are made to the module or class dynamically during the run time.

Conclusion:

As Python is one of the programming languages with immense features, allowing the organizations to develop their business by developing the applications that suit the user requirements, there is a high demand for it. Most of the organizations are looking for individuals who are expertized and skilled in this subject. I am sure these interview questions will definitely help you to crack the interview. All the best!