code: def test_pickle(backend):
      with backend() as be:
          sampler1 = run_sampler(be)
          s = pickle.dumps(sampler1, -1)
          sampler2 = pickle.loads(s)
          for k in ["get_chain", "get_log_prob"]:
              a = getattr(sampler1, k)()
              b = getattr(sampler2, k)()
              assert np.allclose(a, b), "inconsistent {0}".format(k)
  
imports: import pickle
  from itertools import islice, product
  import numpy
  import pytest
  from emcee import EnsembleSampler, backends, moves, walkers_independent
label_desc: Use image node_id 9 for calling a global function with example usage: test_pickle(backend) without return types