class RabbitmqConnectionFactory:
    # ...

    def __enter__(self):
        credentials = pika.credentials.PlainCredentials(
            self.username, self.password
        )
        self.connection = pika.BlockingConnection(
            pika.ConnectionParameters(self.host, self.port, "/", credentials)
        )
        self._make_new_channel()
        return self

    def __exit__(self, exc_type, exc_value, traceback):
        self._close_channel()
        self._close_connection()

    def _make_new_channel(self):
        if self.connection and self.connection.is_open:
            self.channel = self.connection.channel()

    def _close_channel(self):
        if self.channel and not self.channel.is_closed:
            self.channel.close()

    def _close_connection(self):
        if self.connection and not self.connection.is_closed:
            self.connection.close()

    def _get_channel(self):
        if (not self.connection or self.connection.is_closed or
            not self.channel or self.channel.is_closed):
            self.__exit__(None, None, None)
            self.__enter__()
        return self.channel

    # ... rest of the class


    # USE like this ONLY:

    with RabbitmqConnectionFactory(...) as rq:
        rq.declare_queue(...)