input: 
  from Crypto.Cipher import AES
  
  key = b'Sixteen byte key'
  
  def encrypt(plaintext):
      """ Encrypts a given string using AES encryption in ECB mode.
      >>> encrypt(b'This is a test')
      b'\x86X[\x1d{\xb1\xfa-\xff\xb6rC;\xb9\xd2\xb37'
      >>> encrypt(b'Hello, world!')
      b'\xf7?Xb\xe8>?!\xdf.O[=^\xb7(_\x91\xd4$(\x83FA\xe0m'
      """
      cipher = AES.new(key, AES.MODE_ECB)
      return cipher.encrypt(plaintext)
  
  def decrypt(ciphertext):
      """ Decrypts a given string using AES decryption in ECB mode.
      >>> decrypt(b'\x86X[\x1d{\xb1\xfa-\xff\xb6rC;\xb9\xd2\xb37')
      b'This is a test'
      >>> decrypt(b'\xf7?Xb\xe8>?!\xdf.O[=^\xb7(_\x91\xd4$(\x83FA\xe0m')
      b'Hello, world!'
      """
      cipher = AES.new(key, AES.MODE_ECB)
      return cipher.decrypt(ciphertext)
output:     cipher = AES.new(key, AES.MODE_ECB)
      return cipher.decrypt(ciphertext)