Python Coding challenge - Day 795| What is the output of the following Python Code?

 

Code Explanation:

Importing Flask

from flask import Flask

What it does:

Imports the Flask class from the Flask module.

Why:

Flask is a lightweight web framework in Python used to build web applications and APIs.

The Flask class is the main entry point to create a Flask app.

Creating a Flask Application

app = Flask(__name__)

What it does:

Creates an instance of the Flask application.

Explanation of __name__:

__name__ is a special Python variable that stores the name of the current module.

Flask uses it to know where to look for resources like templates and static files.

Why:

This instance (app) will handle incoming web requests and route them to the correct function.

Defining a Route

@app.route("/")

What it does:

This is a decorator that tells Flask which URL should trigger the function that follows.

Explanation:

The "/" route means the root URL (e.g., http://localhost:5000/).

When someone visits this URL, Flask will run the decorated function.

Why:

It’s how you map URLs to functions in Flask (called view functions).

Defining the View Function

def home():

    return "Hello"

What it does:

Defines a Python function named home that returns the string "Hello".

In Flask terms:

This function is a view function — it determines what content to send back to the client’s browser when they visit /.

Why:

Every route in Flask needs a view function to handle the request and send a response.

Checking if the Function is Callable

print(callable(home))

What it does:

Uses Python’s built-in callable() function to check whether home can be called like a function.

Explanation:

In Python, functions are callable objects (meaning you can “call” them using ()).

callable(home) returns True because home is indeed a function.

Expected Output:

True

500 Days Python Coding Challenges with Explanation