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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 subtract_afromb(*inputs, **kwargs):
 """Subtract stream a from stream b. Returns: list(IOTileReading) """


    try:
        value_a = inputs[0].pop()
        value_b = inputs[1].pop()

        return [IOTileReading(0, 0, value_b.value - value_a.value)]
    except StreamEmptyError:
        return []