input: Write a python function to encrypt and decrypt a message using Fernet from the cryptography library.
  assert decrypt_message(encrypt_message("This is a secret message")) == b"This is a secret message"
  assert decrypt_message(encrypt_message("Another message")) == b"Another message"
  assert decrypt_message(encrypt_message("1234567890")) == b"1234567890"
output: from cryptography.fernet import Fernet
  
  # Generate a key for encryption and decryption
  key = Fernet.generate_key()
  cipher_suite = Fernet(key)
  
  def encrypt_message(message: str) -> bytes:
      return cipher_suite.encrypt(message.encode())
  
  def decrypt_message(encrypted_message: bytes) -> bytes:
      return cipher_suite.decrypt(encrypted_message)