message: Delete stray single quote.
diff: @@ -52,7 +52,7 @@ class Aead(object):
  @abc.abstractmethod
  def decrypt(self, ciphertext: bytes, associated_data: bytes) -> bytes:
  - """Decrypts ciphertext' with associated_data.
  + """Decrypts ciphertext with associated_data.
  The decryption verifies the authenticity and integrity of the associated
  data, but there are no guarantees with respect to secrecy of that data.
  