Update app.py

app.py

@@ -47,6 +47,6 @@ class Handler(http.server.BaseHTTPRequestHandler):
         else:
             self.send_error(404)
 
-with socketserver.TCPServer(("", PORT), Handler) as d:
+with socketserver.TCPServer(("0.0.0.0", PORT), Handler) as d:
     print(f"Server: {PORT}")
     d.serve_forever()