code: def setup_method(self):
      self.cohn = load_basic_cohn()
  
imports: from statsmodels.compat.pandas import assert_series_equal, assert_frame_equal
  from io import StringIO
  from textwrap import dedent
  import numpy
  import numpy.testing
  import numpy
  from numpy.testing import assert_equal
  import pandas
  import pytest
  from statsmodels.imputation import ros
label_desc: Use image node_id 1 for calling the Test__ros_plot_pos obj's underlying member method code with example usage: obj.setup_method() without return types