Flask is a “microframework” for Python, and is an excellent choice for building smaller applications, APIs, and web services.

Building an app with Flask is a lot like writing standard Python modules, except some functions have routes attached to them. It’s really beautiful.

Rather than aiming to provide everything you could possibly need, Flask implements the most commonly-used core components of a web application framework, like URL routing, request and response objects, and templates.

If you use Flask, it is up to you to choose other components for your application, if any. For example, database access or form generation and validation are not built-in functions of Flask.

This is great, because many web applications don’t need those features. For those that do, there are many Extensions available that may suit your needs. Or, you can easily use any library you want yourself!

Flask is default choice for any Python web application that isn’t a good fit for Django.

pip3 install --user Flask

from flask import Flask
app = Flask(__name__)


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

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

• https://docs.python-guide.org/scenarios/web/
• https://towardsdatascience.com/deploying-keras-deep-learning-models-with-flask-5da4181436a2