minimal flask application import

from flask import Flask

app = Flask(__name__)

@app.route('/')
def hello():
    return 'Hello, World!'

if __name__ == '__main__':
    app.run()

Explanation:

1. from flask import Flask: Imports the Flask class from the Flask module, allowing us to create a Flask web application.

2. app = Flask(__name__): Creates an instance of the Flask class. The __name__ variable represents the name of the current Python module. This is used by Flask to determine the root path of the application.

3. @app.route('/'): Decorator that creates a mapping between the URL ('/') and the function that handles requests to this URL.

4. def hello():: Defines a function named hello that will be called when the specified route ('/') is accessed.

5. return 'Hello, World!': Returns the string 'Hello, World!' as the response when the '/' route is accessed.

6. if __name__ == '__main__':: Checks if the script is being run directly (not imported as a module).

7. app.run(): Starts the Flask development server to handle incoming requests. The server listens for requests on the default IP address (127.0.0.1) and port (5000).

This code sets up a basic Flask application that responds with 'Hello, World!' when the root URL ('/') is accessed in a web browser or through an HTTP request.