Page Jump and redirection in flask framework

Sample code 1：

from flask import Flask, redirect, url_for

app = Flask(__name__)


@app.route('/')
def index():
    login_url = url_for('login')
    return redirect(login_url)


@app.route('/login')
def login():
    return ' This is the landing page '


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

  Sample code 2：

from flask import Flask, request, redirect, url_for

app = Flask(__name__)


@app.route('/')
def login():
    return 'login'


@app.route('/profile/')
def profile():
    name = request.args.get('name')
    if not name:
        return redirect('http://www.baidu.com')  #  Be careful ： If you write directly here www.baidu.com Redirection is not possible , yes url The joining together of 
    else:
        return redirect(url_for('login'))


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