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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 expo(base=2, factor=1, max_value=None):
 """Generator for exponential decay. Args: base: The mathematical base of the exponentiation operation factor: Factor to multiply the exponentation by. max_value: The maximum value to yield. Once the value in the true exponential sequence exceeds this, the value of max_value will forever after be yielded. """

    n = 0
    while True:
        a = factor * base ** n
        if max_value is None or a < max_value:
            yield a
            n += 1
        else:
            yield max_value