Functions in Python are blocks of organized, reusable code that perform a specific task. They provide modularity and abstraction, allowing you to break down your program into smaller, manageable pieces.

Here's an overview of defining and using functions in Python:

Defining a Function

You can define a function in Python using the def keyword followed by the function name and parentheses () containing any parameters. The function body is indented and contains the code to be executed when the function is called.

Function Parameters

Functions can take zero or more parameters. These parameters are placeholders for the values that will be passed to the function when it is called. Parameters can have default values as well.

Return Statement

Functions can return values using the return statement. This statement exits the function and optionally sends back a value to the caller.

Docstrings

Docstrings are documentation strings that appear as the first statement in a function. They are used to describe what the function does, its parameters, and return values. Docstrings are enclosed in triple quotes (""" """).

Lambda Functions

Lambda functions, also known as anonymous functions, are small, inline functions that are defined using the lambda keyword.

Scope of Variables

Variables defined inside a function have local scope, meaning they can only be accessed within that function. Variables defined outside any function have global scope, meaning they can be accessed from anywhere in the code.

These are the basic concepts of functions in Python. They are crucial for writing organized, maintainable, and scalable code.