Modules are just files that contain Python statements and definitions. A file that contains Python code (for example, sample.py) is called a module and its module name would be sample. Using modules, we can break larger programs into small and organized ones. An important feature of a module is re-usability. Instead of copying the definitions of the most used functions in different programs, you can define them in the module and just import them whenever needed.

Let's create a module and import it. We will create two scripts: sample.py and add.py. We will import a sample module in our add.py. Now, save the following code as sample.py. Let's take a look with the following example:

sample.py
def addition(num1, num2):
    result = num1 + num2
    return result

Here, we have defined a addition() function inside a module named sample. The function takes in two numbers and returns their sum. Now we have created a module. You can import this in any Python program.