python
from itsdangerous import TimedJSONWebSignatureSerializer as Serializer
SECRET_KEY = 'your_secret_key'
data = {'user_id': 12345, 'username': 'example_user'}
token = s.dumps(data).decode('utf-8')
print(f"Generated token: {token}")
try:
data = s.loads(token)
print(f"Valid token: {data}")
except:
print("Invalid token!")
