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# the final bit of the buffer and exit the loop.
if None in data:
stop = True
data.remove(None)

yield b''.join(data)

def _fill_buffer(buff, in_data, frame_count, time_info, status_flags):
"""Continuously collect data from the audio stream, into the buffer."""
buff.put(in_data)
return None, pyaudio.paContinue

# [START audio_stream]
@contextlib.contextmanager
def record_audio(rate, chunk):
"""Opens a recording stream in a context manager."""
# Create a thread-safe buffer of audio data
buff = queue.Queue()

audio_interface = pyaudio.PyAudio()
audio_stream = audio_interface.open(
format=pyaudio.paInt16,
# The API currently only supports 1-channel (mono) audio
# https://goo.gl/z757pE
channels=1, rate=rate,
input=True, frames_per_buffer=chunk,
# Run the audio stream asynchronously to fill the buffer object.
# This is necessary so that the input device's buffer doesn't overflow
# while the calling thread makes network requests, etc.
stream_callback=functools.partial(_fill_buffer, buff),
)

yield _audio_data_generator(buff)

audio_stream.stop_stream()
audio_stream.close()
# Signal the _audio_data_generator to finish
buff.put(None)
audio_interface.terminate()
# [END audio_stream]

def request_stream(data_stream, rate, interim_results=True):

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