Challenge my teacher gave me - make a quick HTTP server to serve as a link shortener using redis and Python. Spedran it in well under an hour not knowing how to use Redis at all

main.html

{% block content %}
<form action='/url/post' method="post">
	<p>URL: <input type="url" name="url"></p>
	<p><button type="submit">Shorten your URL!</button></p>
</form>
{% endblock %}

webserver.py

from flask import Flask, request, redirect, render_template
import redis 
import random 
import time 

r = redis.Redis(host="localhost", port=6379, decode_responses=True)
characters = "abcdefghijklmnopqrstuvwxyz1234567890" 

app = Flask(__name__) 
@app.route("/") 
def home(): 
    return render_template("main.html")

@app.route("/<string:dom>/")
def slashdomain(dom): 
    return domain(dom) 

@app.route("/<string:domain>") 
def domain(domain): 
    if(domain in r.hgetall("links").keys()): 
        r.lpush(domain, int(time.time()))
        return redirect(r.hgetall("links")[domain])
    else: 
        return redirect("/") 

@app.route("/<string:domain>/stats")
def stats(domain): 
    if(domain in r.hgetall("links").keys()): 
        res = "Domain: " + domain  
        res += "\nLong Link: " + r.hgetall("links")[domain]
        entries = r.lrange(domain, 0, -1)
        res += f"\nVisits: {len(entries)}" 
        return res 
    else: 
        return redirect("/") 

@app.route("/<string:domain>/stats/")
def slashstats(dom): 
    return stats(dom) 
    
@app.route("/url/post", methods=["POST"]) 
def url(): 
    try: 
        links = r.hgetall("links")
        if(request.form["url"] in links.values()): 
            res = {i for i in links if links[i] == request.form["url"]}
            return redirect(f"/{list(res)[0]}/stats")
        else: 
            random = randomString() 
            r.hset("links", random, request.form["url"])
            return redirect(f"/{random}/stats")
    except Exception as e: 
        print("EXCEPTION", repr(e))
        return redirect("/")

@app.errorhandler(404)
def notfound(e): 
    return f"YOU BROKE IT {e}"

def randomString(): 
    return ''.join(random.choices(population=characters, k=5))

if __name__ == '__main__':
    app.run(debug = True, host="127.0.0.1", port=8080)