def packet_is_empty(self) -> bool:
        """
        Returns `True` if the current packet is empty.
        """
        assert self._packet is not None
        packet_size = self._buffer.tell() - self._packet_start
        return packet_size <= self._header_size

        Returns `True` if the current packet is empty.
        
src/aioquic/quic/packet_builder.py