Python Built-in Module

In Python, a module is referred to as a file comprising of functions, classes, or variables. It helps us organizing the code logically and reuse it across different programs. There are many Python modules, each with its specific work.

A Python module is a file consisting of Python script (generally, with a .py extension) having definitions of functions, classes, or variables. A module can also include runnable code.

Putting related code into a module makes it easier to read, use again in other programs, and keep everything organized.

To read more Python Modules

What is Python Built-in Modules?

Python Built-in modules are a pre-installed set of libraries. It is quite distracting to install a particular module for a task, as it causes hindrance in the development, so Python comes with some important modules that are most used.

These modules play an important role in development as they provide a wide range of functionalities. "os module", "sys module", and "math module" are some examples of built-in modules in Python.

Types of Python Built-in Modules

1. os Module

Python os module provides the facility to establish the interaction between the user and the operating system. It offers many useful OS functions that are used to perform OS-based tasks and get related information about the operating system.

To work with the OS module, we need to import the OS module.

To read more Python os Module

os Module Functions

2. sys Module

The Python sys module provides functions and variables that are used to manipulate different parts of the Python Runtime Environment. It lets us access system-specific parameters and functions.

To read more Python sys Module

Example: Checking Python Version

Output:

3.13.7 (tags/v3.13.7:bcee1c3, Aug 14 2025, 14:15:11) [MSC v.1944 64 bit (AMD64)]

Explanation

The above code prints the value of the version of the Python Interpreter that is currently in use.

Importance of the sys module

1. It allows us to work with functions and system-specific parameters, such as command-line arguments.
2. It helps us establish control over the functions like sys.exit() and sys.getsizeof() of an interpreter.
3. We can interact with the Python Runtime environment.
4. Makes debugging in the Python code comparatively easier.

3. random Module

In Python, the Random Module is a built-in module that enables us to generate random numbers. It generates Pseudo-random numbers, which means that those numbers are technically not random.

Random objects like numbers, strings, or a list can be generated by the Random Module in Python.

To read more Python random Module

random Module Functions

4. math Module

The Math Module is a built-in module that allows us to use arithmetic operations, complex mathematical calculations like trigonometric functions, logarithms, and exponentials.

To read more Python math Module

Output:

Enter a number:25
The square root of the number is: 5.0

Constants in math Module

The Math Module in Python provides us with the values of several constants that we regularly use in Mathematical contexts.

For example, to find the area of a circle, we have to use pi because the formula is pi*r², where r is the radius of the circle.

Output:

Value of Pi Constant 3.141592653589793
Value of Euler's Constant 2.718281828459045
Value of Tau's Constant 6.283185307179586
Value of Infinity = inf
Value of Not a Number = nan

Python math Module Functions

As we know, the Python Math Module allows us to perform advanced mathematical calculations, such as trigonometric functions, logarithms, and exponentials.

5. Python JSON Module

JSON, which stands for JavaScript Object Notation, is a module that Python offers. Python supports the marshal and pickle modules from the standard library, and JSON API functions similarly to these libraries. Python natively supports JSON characteristics.

We can import the JSON module in Python using:

Output:

['JSONDecodeError', 'JSONDecoder', 'JSONEncoder', '__all__', '__author__', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__path__', '__spec__', '__version__', '_default_decoder', '_default_encoder', 'codecs', 'decoder', 'detect_encoding', 'dump', 'dumps', 'encoder', 'load', 'loads', 'scanner']

Output:

{"Name" : "Peter", "Roll_no" : "0090014" , "Grade" : "A", "Age" : 20, "Subject" : ["Computer Graphics", "Discrete Mathematics", "Data Structure"] }

6. Python datetime Module

The datetime module enables us to create custom date objects, perform various operations on dates, like comparison, etc.

To work with dates as date objects, we have to import the datetime module into the Python source code.

To read more Python datetime Module

Consider the following example to get the datetime object representation for the current time.

Output:

2025-11-04 14:08:00.007276

The datetime classes are classified into six main classes.

• date- It is a naive ideal date. It consists of the year, month, and day as attributes.
• time- It is a perfect time, assuming every day has precisely 24*60*60 seconds. It has hour, minute, second, microsecond, and tzinfo as attributes.
• datetime- It is a grouping of date and time, along with the attribute's year, month, day, hour, minute, second, microsecond, and tzinfo.
• timedelta -It represents the difference between two dates, times, or datetime instances to microsecond resolution.
• tzinfo- It provides time zone information objects.
• Timezone -It is included in the new version of Python. It is the class that implements the tzinfo abstract base class.

How to get the current time?

The localtime() functions of the time module are used to get the current time tuple. Consider the following example.

Example

Output:

time.struct_time(tm_year=2020, tm_mon=4, tm_mday=3, tm_hour=21, tm_min=21, tm_sec=40, tm_wday=4, tm_yday=94, tm_isdst=0)

7. calendar Module

Python provides a calendar object that contains various methods to work with calendars.

Consider the following example to print the calendar for November month of 2025.

Output:

Printing Complete Calendar

The prcal() method of the calendar module is used to print the calendar of the entire year. The year for which the calendar is to be printed must be passed into this method.

Output:

8. tkinter Module

The tkinter module is a built-in module. It is the standard GUI toolkit for Python. It is used in desktop applications to design and create buttons, text boxes, windows, and other UI elements.

Output:

Explanation

In the above code, we imported the Tkinter module as tk and defined a class known as click_on_button. We named the title of the dialogue box as Example of using Tkinter Module. The name of the tile is "Example of using Tkinter Module".

9. hashlib module

The hashlib module is a built-in module in Python which helpful in hashing by providing algorithms like SHA-256, MD5, etc. It also allows for data integrity checks.

Output:

006e62197234b1c4c368acbbd705af138f50066c3bf52af64658b6032a4a3314     

10. heapq module

We can implement the heap queue algorithm by the collection of functions provided by the Heapq module in Python.

Output:

0
1
[9, 8, 8]
[2, 3, 4]

Advantages of Built-in Modules

• Better Efficiency and Less Time: The Python Built-In modules enable users to perform various tasks without writing extra lines of code when they just use the built-in functions. It improves the efficiency and saves efforts and time in the development.
• Optimized Performance: Since these modules in Python are built-in, they are optimized accordingly for most tasks. Hence, it gives optimized performance.
• Reliability: As we already know that Python built-in modules are highly optimized, which makes them automatically reliable as they have gone through rigorous testing by the developers.
• Consistency: The built-in modules in Python provide developers with consistency in development as they can easily understand and use modules across various projects.
• Standardization: Python Built-in modules bring standardization in performing various tasks as they are a part of the standard Python Library.
• Documentation: There is a vast library of documentation of Python, which contains immense knowledge and information regarding bugs, errors, updates, and their fixes. So, if anyone gets stuck during coding, the documentation is always there to help.
• Maintainability: The Python Built-in modules are regularly maintained the updated by the vast community of researchers, programmers, and core team members of Python. It ensures long-term viability and relevancy.
• Reduced Risk: As the modules are built-in and approved by the developers, it reduces the risks that are usually caused by third-party modules.

Conclusion

In this tutorial, we learnt about the built-in modules in Python. Python Built-in modules are a pre-installed set of libraries in the Python installation. It is quite distracting to install a particular module for a task, as it causes hindrance in the development, so Python comes with some important modules that are most used. These modules play an important role in development as they provide a wide range of functionalities. We studied in detail the various modules like os, sys, JSON, random, tkinter, math, datetime, calendar, hashlib, and heapq modules.