Summary of steps to create a web application with Python + Flask

programming

Do you want to create your own web app, but don't know where to start?
For those people, we recommend creating a simple web app using Python and Flask.

Python is easy for beginners to understand, and Flask is a lightweight, easy-to-learn framework.
This article will explain in detail the steps required to create a web application.

The steps are explained with code, so anyone can create a working app in no time!

Explaining what Python and Flask are

Why Flask is great for web apps

Conclusion: With Python and Flask, you can build web apps with very little code.

reason:

  • Python is easy to read
  • Flask is lightweight and flexible
  • Easy to use even for beginners

For example, it has the following features:

  • You can build an app with just one file
  • Low learning cost
  • Easy to extend functionality later

This makes Flask a great choice for both learning and production.

Prepare your Flask development environment

Installing Python and Flask

Follow the steps below to set up your development environment.

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# Install Python (from the official website)
 
<a rel="noopener" href="https://www.python.org/" title="Welcome to Python.org" class="blogcard-wrap external-blogcard-wrap a-wrap cf" target="_blank"><div class="blogcard external-blogcard eb-left cf"><div class="blogcard-label external-blogcard-label"><span class="fa"></span></div><figure class="blogcard-thumbnail external-blogcard-thumbnail"><img decoding="async" src="https://www.python.org/static/opengraph-icon-200x200.png" alt="" class="blogcard-thumb-image external-blogcard-thumb-image" width="160" height="90"></figure><div class="blogcard-content external-blogcard-content"><div class="blogcard-title external-blogcard-title">Welcome to Python.org</div><div class="blogcard-snippet external-blogcard-snippet">The official home of the Python Programming Language</div></div><div class="blogcard-footer external-blogcard-footer cf"><div class="blogcard-site external-blogcard-site"><div class="blogcard-favicon external-blogcard-favicon"><img decoding="async" src="https://www.google.com/s2/favicons?domain=https://www.python.org/" alt="" class="blogcard-favicon-image external-blogcard-favicon-image" width="16" height="16"></div><div class="blogcard-domain external-blogcard-domain">www.python.org</div></div></div></div></a>
 
# Create a virtual environment python -m venv venv source venv/bin/activate # For Windows venv\Scripts\activate # Install Flask pip install flask

By using a virtual environment, other projects will not be affected.

Design the web app configuration

Minimal directory configuration

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myapp/ ├── app.py └── templates/ └── index.html

Start with a small number of files and proceed while checking that it works.

Creating basic routing with Flask

Code to display "Hello, World!"

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from flask import Flask app = Flask(__name__) @app.route("/") def hello(): return "Hello, World!" if __name__ == "__main__": app.run(debug=True)

In your browser http://localhost:5000 You can see it by accessing.

Embedding HTML Templates

Displaying dynamic pages with Jinja2

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from flask import Flask, render_template app = Flask(__name__) @app.route("/") def index(): return render_template("index.html")
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<!-- templates/index.html --><title>Flask App</title><h1> Welcome to the Flask web app</h1>

This will allow you to load static HTML as well.

How to receive form input

Receiving POST submissions

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from flask import request @app.route("/submit", methods=["POST"]) def submit(): name = request.form.get("name") return f"Thank you, {name}, for submitting your request!"

It can process form input and display the response dynamically.

Common errors and their solutions

  • ModuleNotFoundError: No module named 'flask'
    → Flask needs to be installed.pip install flask Don't forget.
  • jinja2.exceptions.TemplateNotFound
    → Templates Make sure you have placed the HTML in the folder.

Completed code (app.py)

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from flask import Flask, render_template, request app = Flask(__name__) @app.route("/") def index(): return render_template("index.html") @app.route("/submit", methods=["POST"]) def submit(): name = request.form.get("name") return f"Thank you, {name}!

Summary: Python + Flask is the best introductory environment

  • Create web apps with Python and Flask
  • Beginner-friendly syntax
  • Forms and HTML can be easily integrated
  • Environment construction is simple

Let's start by displaying "Hello, World!".
Next, try out database integration and login functions!

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