input: from Crypto.Cipher import AES
  
  key = b'Sixteen byte key'
  
  def encrypt(plaintext):
      cipher = AES.new(key, AES.MODE_ECB)
      return cipher.encrypt(plaintext)
  
  def decrypt(ciphertext):
      cipher = AES.new(key, AES.MODE_ECB)
      return cipher.decrypt(ciphertext)
  
  """
  Create an application in Python for encryption and decryption of strings. The application should take a string as input, and use a cipher text algorithm of choice to encrypt the string.
  Example:
  >>> encrypted_text = encrypt(b'Hello, World!')
  >>> encrypted_text
  b'...\x0e\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
  >>> decrypted_text = decrypt(encrypted_text)
  >>> decrypted_text
  b'Hello, World!'
  """
output:     if len(plaintext) % 16 != 0:
          plaintext = plaintext.ljust(len(plaintext) + (16 - len(plaintext) % 16), b'\0')
      return cipher.encrypt(plaintext)
  
  def decrypt(ciphertext):
      cipher = AES.new(key, AES.MODE_ECB)
      decrypted_text = cipher.decrypt(ciphertext)
      return decrypted_text.rstrip(b'\0')