code: def normalize_cutoff(model, zero_cutoff=None):
      
      if zero_cutoff is None:
          return model.tolerance
      else:
          if zero_cutoff < model.tolerance:
              raise ValueError(
                  "The chosen zero cutoff cannot be less than the model's "
                  "tolerance value."
              )
          else:
              return zero_cutoff
docs: Return a valid zero cutoff value.