code: def setUp(self):
      window_selector_model = realigner_pb2.WindowSelectorModel(
          model_type=realigner_pb2.WindowSelectorModel.ALLELE_COUNT_LINEAR,
          allele_count_linear_model=realigner_pb2.WindowSelectorModel.AlleleCountLinearModel(
              bias=0,
              coeff_soft_clip=0,
              coeff_substitution=-0.5,
              coeff_insertion=1,
              coeff_deletion=1,
              coeff_reference=-0.5,
              decision_boundary=0,
          ),
      )
      self.config = realigner_pb2.WindowSelectorOptions(
          min_mapq=20,
          min_base_quality=20,
          min_windows_distance=4,
          region_expansion_in_bp=20,
          window_selector_model=window_selector_model,
      )
  
imports: from absl.testing import absltest
  from absl.testing import parameterized
  from third_party.nucleus.io import fasta
  from third_party.nucleus.testing import test_utils
  from third_party.nucleus.util import ranges
  from deepvariant.protos import realigner_pb2
  from deepvariant.realigner import window_selector
label_desc: Use image node_id 1 for calling the AlleleCountLinearWindowSelectorTest obj's underlying member method code with example usage: obj.setUp() without return types