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Py Functions — Free Python Tutorial

Learn Py Functions in Python with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.

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TL;DR: Learn Py Functions in Python with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.

Written & reviewed by the Syllab.in Academic Team (CBSE/NCERT subject experts) · Updated Jul 14, 2026

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Py Functions in Python

A function is a named, reusable block of code defined with the def keyword. Functions help you avoid repeating code (DRY — Don't Repeat Yourself), organize your program, and make it easy to test individual parts.

Functions can take parameters (inputs) and return values (output). Parameters can have default values. *args collects extra positional arguments as a tuple, **kwargs collects extra keyword arguments as a dict.

Lambda functions (lambda x: x*2) are small anonymous functions for simple operations, often used with map(), filter(), and sorted().

Py Functions — Syntax

def function_name(param1, param2=default):
    # code
    return result

result = function_name(value1, value2)

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