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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)

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