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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 evidence_random_noise_prior(evidence, type_probs, subtype_probs):
 """Determines the random-noise prior probability for this evidence. If the evidence corresponds to a subtype, and that subtype has a curated prior noise probability, use that. Otherwise, gives the random-noise prior for the overall rule type. """

    (stype, subtype) = tag_evidence_subtype(evidence)
    # Get the subtype, if available

    # Return the subtype random noise prior, if available
    if subtype_probs is not None:
        if stype in subtype_probs:
            if subtype in subtype_probs[stype]:
                return subtype_probs[stype][subtype]

    # Fallback to just returning the overall evidence type random noise prior
    return type_probs[stype]