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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def create_noise(length, level=4):
 """Create white noise for background"""

    noise = bytearray(length)
    adjust = 128 - int(level / 2)
    i = 0
    while i < length:
        v = random.randint(0, 256)
        noise[i] = v % level + adjust
        i += 1
    return noise