code: def decrypt(self, encrypted_number):
          
          relevant_private_key = self.__keyring[encrypted_number.public_key]
          return relevant_private_key.decrypt(encrypted_number)
docs: Return the decrypted & decoded plaintext of *encrypted_number*.
  
          Args:
            encrypted_number (EncryptedNumber): encrypted against a known public
              key, i.e., one for which the private key is on this keyring.
  
          Returns:
            the int or float that *encrypted_number* was holding. N.B. if
            the number returned is an integer, it will not be of type
            float.
  
          Raises:
            KeyError: If the keyring does not hold the private key that
              decrypts *encrypted_number*.