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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 _chance(solution, pdf):
 """Return the chance of obtaining a solution from a pdf. The probability of many independant weighted "coin flips" (one for each bit) """

    # 1.0 - abs(bit - p) gives probability of bit given p
    return _prod([1.0 - abs(bit - p) for bit, p in zip(solution, pdf)])