code: async def get_reader(self, source=FFMPEG_STDOUT) -> asyncio.StreamReader:
          
          reader = asyncio.StreamReader(loop=self._loop)
          reader_protocol = asyncio.StreamReaderProtocol(reader)
  
          # Attach stream
          if source == FFMPEG_STDOUT:
              await self._loop.connect_read_pipe(
                  lambda: reader_protocol, self._proc.stdout
              )
          else:
              await self._loop.connect_read_pipe(
                  lambda: reader_protocol, self._proc.stderr
              )
  
          # Start reader
          return reader
docs: Create and return streamreader.