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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 ceilpow2(n):
 """convenience function to determine a power-of-2 upper frequency limit"""

    signif,exponent = frexp(n)
    if (signif < 0):
        return 1;
    if (signif == 0.5):
        exponent -= 1;
    return (1) << exponent;