render_template.py

from flask import Flask, render_template

app = Flask(__name__)

@app.route('/')
def hello_world():
    return render_template("first_page.html")

@app.route('/second')
def hello_world_fancy():
    return render_template("second_page.html")

@app.route('/jinja2/')
def jinja2():
    return render_template("jinja_intro.html", name="Bob Smith", template_name="Jinja2")