code: def test_Rhat(self):
      with self.model:
          idata = to_inference_data(self.trace[self.burn :])
      rhat = az.rhat(idata)
      for var in rhat:
          npt.assert_allclose(rhat[var], 1, rtol=0.01)
  
imports: import arviz
  import numpy
  import numpy.testing
  import pytensor.tensor
  from scipy import stats
  import pymc
  from pymc.backends.arviz import to_inference_data
  from pymc.util import get_var_name
label_desc: Use image node_id 3 for calling the BaseSampler obj's underlying member method code with example usage: obj.test_Rhat() without return types