在哪里可以找到getLevel()?

在下面的代码中使用 getLevel() . 我在哪里能找到它(关于声音,它和pyaudio库一起运行)

# this is the threshold that determines whether or not sound is detected
THRESHOLD = 0

#open your audio stream    

# wait until the sound data breaks some level threshold
while True:
    data = stream.read(chunk)
    # check level against threshold, you'll have to write getLevel()
    if getLevel(data) > THRESHOLD:
        break

# record for however long you want
# close the stream