input: 
  from Crypto.Cipher import AES
  
  key = b'Sixteen byte key'
  
  def encrypt(plaintext: str) -> bytes:
      """Encrypts the given plaintext using AES encryption in ECB mode.
      >>> encrypt('Hello, World!')
      b'sOMqQvyDee7cbbxgIhouqA=='
      """
  
  def decrypt(ciphertext: bytes) -> str:
      """Decrypts the given ciphertext using AES decryption in ECB mode.
      >>> decrypt(b'sOMqQvyDee7cbbxgIhouqA==')
      'Hello, World!'
      """
  
output:     
      cipher = AES.new(key, AES.MODE_ECB)
      padded_plaintext = plaintext.encode() + b'\0' * (AES.block_size - len(plaintext.encode()) % AES.block_size)
      encrypted_text = cipher.encrypt(padded_plaintext)
      return base64.b64encode(encrypted_text)
  