Doc: https://pythonhosted.org/Flask-Bootstrap/

pip install flask_bootstrap

from flask import Flask, render_template
from flask_bootstrap import Bootstrap
 
app = Flask(__name__)
Bootstrap(app)
 
@app.route('/')
def index():
    return render_template('index.html')
 
if __name__ == '__main__':
    app.run(debug=True)

{% extends "bootstrap/base.html" %}
 
{% block title %}Exemple{% endblock %}
 
{% block content %}
<h1>Hello !!!</h1>
{% endblock %}

Voir la liste complète

• title
• styles
• navbar
• content
• scripts
• …