code: def test_exact_ties(self):
      adj_models = self.models_df - 100.0
      adj_models.iloc[:, :2] -= adj_models.iloc[:, :2].mean()
      adj_models.iloc[:, :2] += self.benchmark_df.mean().iloc[0]
      stepm = StepM(self.benchmark_df, adj_models, size=0.10)
      stepm.compute()
      assert_equal(len(stepm.superior_models), self.models.shape[1] - 2)
  
imports: from typing import NamedTuple
  import numpy
  from numpy import linspace
  from numpy.random import RandomState
  from numpy.testing import assert_allclose, assert_equal
  import pandas
  from pandas.testing import assert_frame_equal, assert_series_equal
  import pytest
  import scipy.stats
  from arch.bootstrap import CircularBlockBootstrap, MovingBlockBootstrap, StationaryBootstrap
  from arch.bootstrap.multiple_comparison import MCS, SPA, StepM
label_desc: Use image node_id 8 for calling the TestStepM obj's underlying member method code with example usage: obj.test_exact_ties() without return types