def binary(self):
    """Load and return the path to the native engine binary."""
    lib_name = '{}.so'.format(NATIVE_ENGINE_MODULE)
    lib_path = os.path.join(safe_mkdtemp(), lib_name)
    try:
      with closing(pkg_resources.resource_stream(__name__, lib_name)) as input_fp:
        # NB: The header stripping code here must be coordinated with header insertion code in
        #     build-support/bin/native/bootstrap_code.sh
        engine_version = input_fp.readline().decode('utf-8').strip()
        repo_version = input_fp.readline().decode('utf-8').strip()
        logger.debug('using {} built at {}'.format(engine_version, repo_version))
        with open(lib_path, 'wb') as output_fp:
          output_fp.write(input_fp.read())
    except (IOError, OSError) as e:
      raise self.BinaryLocationError(
        "Error unpacking the native engine binary to path {}: {}".format(lib_path, e),
        e)
    return lib_path
Load and return the path to the native engine binary.