encoding/decoding data in python using the cryptography, dotenv libraries

encode_decode.py

import os
import json
import time
from dotenv import load_dotenv
from cryptography.fernet import Fernet
load_dotenv()
timestamp = time.time()
my_secret_key = str.encode(os.getenv('email_confirmation_secret_key'))
crypto = Fernet(my_secret_key)

user_dict_start = {'email':'john@gmail.com','first_name':'John', 'timestamp': timestamp}
json_bytearray = str.encode(json.dumps(user_dict_start))
token = crypto.encrypt(json_bytearray)

crypto = Fernet(my_secret_key)
returned_bytearray = crypto.decrypt(token)
user_dict_end = json.loads(returned_bytearray.decode())