templates/layout.html
<!doctype html>
<html>
<head>
<title>{{ title }}</title>
</head>
<body>
{% block content %}
{% endblock %}
</body>
</html>
templates/hello.html
{% extends "layout.html" %}
{% block content %}
<h3></h3>
こんにちは。{{ name }}さん。
{% endblock %}
hello.py
from flask import Flask, render_template
app = Flask(__name__)
@app.route('/')
def hello():
name = "Hoge"
return render_template('hello.html', title='flask test', name=name)
if __name__ == "__main__":
app.run(debug=True, host='192.168.56.10', port=8000)
