code: def test_single_blob(self):
      sampler = emcee.EnsembleSampler(6, 1, lambda x: (-(x**2), 3))
      sampler.run_mcmc(np.random.normal(size=(6, 1)), 20)
      inference_data = from_emcee(
          sampler, blob_names=["blob"], blob_groups=["blob_group"]
      )
      fails = check_multiple_attrs(
          {"blob_group": ["blob"]}, inference_data
      )
      assert not fails
  
imports: import os
  import numpy
  import pytest
  from ...None import from_emcee
  from ..helpers import _emcee_lnprior
  from ..helpers import _emcee_lnprob
  from ..helpers import chains, check_multiple_attrs, draws, eight_schools_params, importorskip, load_cached_models, needs_emcee3_func
label_desc: Use image node_id 10 for calling the TestDataEmcee obj's underlying member method code with example usage: obj.test_single_blob() without return types