Python Flask Proxy (almost)

foxy.py

#!/usr/bin/env python
# NOTE: pass -d to this to print debugging info when the server crashes.
from flask import Flask, render_template, request, abort, Response, redirect
import sys, urllib.request, re

app = Flask(__name__.split('.')[0])

@app.route('/<path:url>')
def proxy(url):
    print("Connecting to " + url + "...")
    req = urllib.request.urlopen(url)
    try:
        page = req.read().decode('utf-8')
        page = re.sub('href="http(s)?://(.*?)"', 'href="http://localhost/http://\\2"', page)
        page = re.sub('href="/(.*?)"', 'href="http://localhost/' + url + '/\\1"', page)
        page = re.sub('src="http(s)?://(.*?)"', 'src="http://localhost/http://\\2"', page)
        page = re.sub('src="/(.*?)"', 'src="http://localhost/' + url + '/\\1"', page)
        #page = page.replace('href="https', 'href="http')
        #page = page.replace('src="https', 'src="http')
        return page
    except:
        return req.read()

if __name__ == '__main__':
    print('Starting server...')
    app.run(port=80, debug='-d' in sys.argv[1:])