##two main categories for encryption according key:
#1.symmetric key:the data is encrypted and decryted using the same key
#fernet , AES
#2.asymmetric key:the data is encrypted and decryted using two key
  #1.public key :used for encryption
  #2.private key :used for decryption
  # RSA

#fernet
#1.generate to encryption
#2.use encrypt or decrypt

#example
from cryptography.fernet import Fernet
#key generating
key = Fernet.generate_key()
#text
text = "facebook"
encrypted_text = Fernet(key).encrypt(text.encode())
print(encrypted_text)
print(len(encrypted_text))
decrypted_text = Fernet(key).decrypt(encrypted_text)
print(decrypted_text.decode())