Python Modules

Python Module has built-in functions, classes, and variables. There are several Python modules and each has their specific work. This article has listed the Python modules.

What is a Python Module?

The Python module consists of a file that has Python definitions and statements. A module will then define functions, classes, and variables. Additionally, the module has a runnable code.

Hence, categorizing the module will make the code easier to analyze. Therefore, the code will be more organized.

Create a Module

a.Create a new file, e.g., my_module.py.

b.Define your module content inside this file.

# File: my_module.py

def greet(name):
    """A simple function to greet the user."""
    return f"Hello, {name}! Welcome to my_module."

The syntax is given below:

import module

Use a Module

You will use the module that was created through the import statement.

# File: main_script.py
import my_module

# Using the greet function from my_module
name = "User"
message = my_module.greet(name)
print(message)

When you run main_script.py, it will import the my_module and take the greet function to print a welcome message.

These two files (my_module.py and main_script.py) are placed in the same directory where Python can find them.

Output

Hello, User! Welcome to my_module.

What are the examples of Importing Modules in Python?

The example illustrated below will import the calc for executing the add operation.

# File: main_script.py
import my_module

# Using the greet function from my_module
name = "User"
greeting_message = my_module.greet(name)
print(greeting_message)

# Using the add_numbers function from my_module
result = my_module.add_numbers(5, 7)
print(f"The result of addition is: {result}")

Output

Hello, User! Welcome to my_module.
The result of addition is: 12

How to Import Specific Attributes From a Python Module?

Let us look into the example given below :

# File: main_script.py
from math import sqrt, factorial

# Using the sqrt function from math
number = 25
square_root = sqrt(number)
print(f"The square root of {number} is: {square_root}")

# Using the factorial function from math
fact_number = 5
factorial_result = factorial(fact_number)
print(f"The factorial of {fact_number} is: {factorial_result}")

Output

The square root of 25 is: 5.0
The factorial of 5 is: 120

What is * Import symbol?

The * symbol is used to import the statement function to import all the names from the module to the current namespace.

The syntax is given below

from module_name import *

Note:

The * symbol has its benefits and drawbacks. Suppose the purpose is known to you. However, it is not advised to use *.

# File: main_script.py
from math import sqrt, factorial

# Using the sqrt function from math
number = 25
square_root = sqrt(number)
print(f"The square root of {number} is: {square_root}")

# Using the factorial function from math
fact_number = 5
factorial_result = factorial(fact_number)
print(f"The factorial of {fact_number} is: {factorial_result}")

Output

The square root of 25 is: 5.0
The factorial of 5 is: 120

Locate Python Module

1. Current Directory:
   • First, Python checks if the module is in the same folder where your Python script is located.
2. PYTHON PATH:
   • If it’s not in the current folder, Python checks other places listed in the PYTHON PATH variable.
   • PYTHON PATH is like a list of folders where Python looks for modules. You can add more folders to this list if needed.
3. Installation-Dependent Directories:
   • If the module is still not found, Python checks places to set up when Python was installed.
   • These are special folders that come with Python and contain important modules that are needed for many programs.

What is the Directories List For Modules?

The sys. path has a built-in variable within the sys module. It has a list of directories, in which the interpreter will search in the particular module.

# File: main_script.py
import sys

# Now you can use functions and variables from the sys module
print("Python version:")
print(sys.version)
print("")

print("System platform:")
print(sys.platform)

Output

Python version:
3.8.5 (default, Jan 27 2021, 15:41:15)
[GCC 9.3.0]

System platform:
linux

How to Rename the Python Module?

The Python module will rename the module by importing it with the keyword.

The syntax is provided below

Syntax:  Import Module_name as Alias_name

# File: main_script.py
import math

# Using the sqrt function from math
number = 18  # Change the number to 18
square_root = math.sqrt(number)
print(f"The square root of {number} is: {square_root}")

# Using the factorial function from math
fact_number = 5
factorial_result = math.factorial(fact_number)
print(f"The factorial of {fact_number} is: {factorial_result}")

Output

The square root of 18 is: 4.242640687119285
The factorial of 5 is: 120

What is Python Built-in Modules?

Python consists of built-in modules that allow them to import whenever required.

# File: main_script.py
import math

# Using the sqrt function from math
number = 25
square_root = math.sqrt(number)
print(f"The square root of {number} is: {square_root}")

# Using the factorial function from math
fact_number = 5
factorial_result = math.factorial(fact_number)
print(f"The factorial of {fact_number} is: {factorial_result}")

# Using the pi function from math
pi_value = math.pi
print(f"The value of pi is: {pi_value}")

# Converting 2 radians to degrees
radians_to_degrees = math.degrees(2)
print(f"2 radians in degrees is: {radians_to_degrees}")

# Converting 60 degrees to radians
degrees_to_radians = math.radians(60)
print(f"60 degrees in radians is: {degrees_to_radians}")

# Calculating sine of 2 radians
sine_value = math.sin(2)
print(f"The sine of 2 radians is: {sine_value}")

# Calculating cosine of 0.5 radians
cosine_value = math.cos(0.5)
print(f"The cosine of 0.5 radians is: {cosine_value}")

# Calculating tangent of 0.23 radians
tangent_value = math.tan(0.23)
print(f"The tangent of 0.23 radians is: {tangent_value}")

Output

The square root of 25 is: 5.0
The factorial of 5 is: 120
The value of pi is: 3.141592653589793
2 radians in degrees is: 114.59155902616465
60 degrees in radians is: 1.0471975511965979
The sine of 2 radians is: 0.9092974268256817
The cosine of 0.5 radians is: 0.8775825618903728
The tangent of 0.23 radians is: 0.23414336235146526

Conclusion

To conclude, this article has offered the information about the Python Modules. It has also included how to create the module, Python import from the module, Renaming the Python Module, and several others.

Python Modules-FAQs