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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 fibo(max_value=None):
 """Generator for fibonaccial decay. Args: max_value: The maximum value to yield. Once the value in the true fibonacci sequence exceeds this, the value of max_value will forever after be yielded. """

    a = 1
    b = 1
    while True:
        if max_value is None or a < max_value:
            yield a
            a, b = b, a + b
        else:
            yield max_value