from flask import Flask, redirect, request  app = Flask(__name__)  from urllib.parse import urlparse, urlunparse  FROM_DOMAIN = "yourusername.pythonanywhere.com" TO_DOMAIN = "www.yourdomain.com"  @app.before_request def redirect_to_new_domain():     urlparts = urlparse(request.url)     if urlparts.netloc == FROM_DOMAIN:         urlparts_list = list(urlparts)         urlparts_list[1] = TO_DOMAIN         return redirect(urlunparse(urlparts_list), code=301) 

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