from flask import Flask,make_response,redirect,abort
app = Flask(__name__)

@app.route(‘/index1‘)
def index1():
    return make_response(‘<h1>Bad Request</h1>‘, 400)

@app.route(‘/index2‘)
def index2():
    return ‘<h1>Bad Request</h1>‘, 400

@app.route(‘/index3‘)
def index3():
    return redirect(‘http://www.baidu.com‘)

@app.route(‘/index4‘)
def index4():
    return abort(404)

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