What libraries or frameworks do you use for developing graphical or web interfaces in Python?

For developing graphical user interfaces in Python, the following libraries and frameworks are commonly used:

• Tkinter — the standard library for creating simple GUI applications.
• PyQt and PySide — powerful frameworks based on Qt, suitable for complex and cross-platform applications.
• Kivy — for creating multi-touch and mobile interfaces.
• wxPython — a wrapper over wxWidgets, cross-platform GUI.

For web interfaces, popular options include:

• Django — a full framework for web applications with templates and ORM.
• Flask — a lightweight microframework for web development.
• FastAPI — a modern framework for building APIs with high performance.

Example of a simple web app in Flask:

from flask import Flask
app = Flask(__name__)

@app.route('/')
def home():
    return "Hello, world!"

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