in FLASK how to map the relative Url code example

Example 1: flask site route

from flask import render_template

@app.route('/hello/')
@app.route('/hello/<name>')
def hello(name=None):
    return render_template('hello.html', name=name)
  
---------------------------------------------------
<!doctype html>
<title>Hello from Flask</title>
{% if name %}
  <h1>Hello {{ name }}!</h1>
{% else %}
  <h1>Hello, World!</h1>
{% endif %}

Example 2: flask app.route

@app.route("/route/to/page")
def what_to_display_when_someone_goes_here():
    return("Whatever.")