message: Return without writing output in case of error in Python AEAD CLI.
diff: @@ -109,11 +109,13 @@ def main(argv):
  output_data = cipher.encrypt(input_data, aad)
  except tink.TinkError as e:
  logging.error('Error encrypting the input: %s', e)
  + return 1
  elif operation.lower() == 'decrypt':
  try:
  output_data = cipher.decrypt(input_data, aad)
  except tink.TinkError as e:
  logging.error('Error decrypting the input: %s', e)
  + return 1
  else:
  logging.error(
  'Did not recognise operation %s.\n'
  