class_docstr: Basic tests for the wrapped DeBruijnGraph class.
docstr: This is a regression test for internal.
docstr_tok: ["This","is","a","regression","test","for","internal","."]
code: def test_k_exceeds_ref_length(self):
      """This is a regression test for internal."""
      # We don't allow a k >= ref length.  This crashed prior to the bugfix.
      ref_str = "GATTACA"
      dbg = debruijn_graph.build(
          ref_str, [], self.single_k_dbg_options(7)
      )
      self.assertIsNone(dbg)
      dbg = debruijn_graph.build(
          ref_str, [], self.single_k_dbg_options(8)
      )
      self.assertIsNone(dbg)
  
imports: from absl.testing import absltest
  from absl.testing import parameterized
  from third_party.nucleus.io import fasta
  from third_party.nucleus.io import sam
  from third_party.nucleus.testing import test_utils
  from third_party.nucleus.util import ranges
  from deepvariant import testdata
  from deepvariant.protos import realigner_pb2
  from deepvariant.realigner.python import debruijn_graph
label_desc: Use image node_id 11 for calling the DeBruijnGraphWrapTest obj's underlying member method code with example usage: obj.test_k_exceeds_ref_length() without return types