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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def protocol_authenticate(self, account=None):
 """ Low-level API to perform protocol-level authentication on protocols that support it. .. HINT:: In most cases, you want to use the login() method instead, as it automatically chooses the best login method for each protocol. :type account: Account :param account: An account object, like login(). """

        with self._get_account(account) as account:
            user = account.get_name()
            password = account.get_password()
            key = account.get_key()
            if key is None:
                self._dbg(1, "Attempting to authenticate %s." % user)
                self._protocol_authenticate(user, password)
            else:
                self._dbg(1, "Authenticate %s with key." % user)
                self._protocol_authenticate_by_key(user, key)
        self.proto_authenticated = True