What is a module? Why and How are they used in Python?

MODULE

In a Python, a module can be defined as a python program file, which contains a python code including python functions. It is essentially a python script file that can contain variables,functions, and classes. The variables can be of any type (array, dictionaries, objects etc.)                            

 Modules can be divided into two sub parts :-

• Built in

• User-defined

1) User-defined Modules

Create a Module:- To create a module, create a Python file with a .py extension.

Call a Module:- Modules created with a .py extension can be used in another Python source file, using the import statement.

#callModule.py

import myModule

myModule.myFunction("Python Programming")

2) Built-in Modules

There are several built-in modules in Python, which you can import whenever you like.

Call a built-in Module:- To call a built-in Module and use the function of that module write:

import moduleName #call a module
moduleName.function()#use module function

import math

print("The value of cosine is", math.cos(3))

print("The value of sine is", math.sin(3))

print("The value of tangent is", math.tan(3))

print("The value of pi is", math.pi)

WHY MODULES USED?

There are couple of key that describe the use of modules in python:-

     Structured Code

• Code is logically organized by being grouped into one Python file which makes development easier and less error-prone.
• Code is easier to understand and use.

     Reuse ability

• Functionality defined in a single module can be easily reused by other parts of the application. This eliminates the need to recreate duplicate code.

HOW THEY ARE USED?

To create a module just save the code you want in a file with the file extension .py:

Example

Save this code in a file named mymodule.py

def greeting(name):
  print("Hello, " + name)

Now we can use the module we just created, by using the import statement:

Example

Import the module named mymodule, and call the greeting function:

import mymodule

mymodule.greeting("Royal")

The Output is:- Hello, Royal