Introducing Common Python Functions: A Beginner’s Guide

The author starts by pointing out a requirement to output numbers 1‑10 in ten places, which leads to duplicated code and maintenance difficulties.

To address this, the article introduces the concept of functions in Python, explaining that a function encapsulates frequently used logic for easier reuse and maintenance.

It outlines the syntax: def function_name(parameters): followed by an indented function body, and lists key rules such as using the def keyword, separating declaration and implementation, naming conventions, optional parameters, indentation, and the need to call the function after its definition.

An example demonstrates a simple loop printing numbers 1‑10 using for i in range(1, 11): print(i). The same loop is shown three times to illustrate redundancy.

The article then defines a function def test(): that iterates from 1 to 10 and prints only odd numbers using if i % 2 == 1:. Calling test() produces the odd numbers 1,3,5,7,9.

Finally, the output of the repeated loops is displayed, showing the numbers 1‑10 printed multiple times, reinforcing why encapsulating the logic in a function is preferable.