code: def setUp(self):
      self.sites_vcf = test_utils.genomics_core_testdata(
          "test_sites.vcf"
      )
      self.samples_vcf = test_utils.genomics_core_testdata(
          "test_samples.vcf.gz"
      )
      self.options = variants_pb2.VcfReaderOptions()
      self.sites_reader = vcf_reader.VcfReader.from_file(
          self.sites_vcf, self.options
      )
      self.samples_reader = vcf_reader.VcfReader.from_file(
          self.samples_vcf, self.options
      )
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from absl.testing import absltest
  from third_party.nucleus.io.python import vcf_reader
  from third_party.nucleus.protos import reference_pb2
  from third_party.nucleus.protos import variants_pb2
  from third_party.nucleus.testing import test_utils
  from third_party.nucleus.util import ranges
label_desc: Use image node_id 1 for calling the WrapVcfReaderTests obj's underlying member method code with example usage: obj.setUp() without return types