code: def setup_method(self):
      # fit for each test, because results will be changed by test
      np.random.seed(987689)
      data = sm.datasets.randhie.load()
      mod = sm.NegativeBinomial(data.endog, data.exog)
      self.results = mod.fit(disp=0)
  
imports: from statsmodels.compat.pandas import assert_series_equal
  from io import BytesIO
  import pickle
  import numpy
  import pandas
  import statsmodels.api
label_desc: Use image node_id 1 for calling the TestRemoveDataPickleNegativeBinomial obj's underlying member method code with example usage: obj.setup_method() without return types