code: def test_from_file_raises_with_missing_gff(self):
      # TODO: OpError exception not propagated.
      with self.assertRaisesRegexp(
          ValueError, "Could not open missing.gff"
      ):
          gff_reader.GffReader.from_file("missing.gff", self.options)
  
file_path: deepvariant/third_party/nucleus/io/python/gff_reader_wrap_test.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from absl.testing import absltest
  from absl.testing import parameterized
  from third_party.nucleus.io import clif_postproc
  from third_party.nucleus.io.python import gff_reader
  from third_party.nucleus.protos import gff_pb2
  from third_party.nucleus.testing import test_utils
label_desc: Use image node_id 3 for calling the GffReaderTest obj's underlying member method code with example usage: obj.test_from_file_raises_with_missing_gff() without return types