code: def evidence_random_noise_prior(evidence, type_probs, subtype_probs):
      
      (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]
docs: 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.