How to use the opencensus.trace.span_data.SpanData function in opencensus

def test_basic_spans_emit(self):
        hex_encoder = codecs.getencoder('hex')
        client = mock.Mock()
        client.Export.return_value = iter([1])

        span_data0 = span_data_module.SpanData(
            name="name0",
            context=span_context_module.SpanContext(
                trace_id='0e0c63257de34c92bf9efcd03927272e'),
            span_id='0e0c63257de34c92',
            parent_span_id=None,
            start_time=None,
            end_time=None,
            attributes=None,
            child_span_count=None,
            stack_trace=None,
            time_events=None,
            links=None,
            status=None,
            same_process_as_parent_span=None,
            span_kind=0)

def test_emit(self, monitor_resource_mock):
        trace_id = '6e0c63257de34c92bf9efcd03927272e'
        span_datas = [
            span_data_module.SpanData(
                name='span',
                context=span_context.SpanContext(trace_id=trace_id),
                span_id='1111',
                parent_span_id=None,
                attributes=None,
                start_time=None,
                end_time=None,
                child_span_count=None,
                stack_trace=None,
                time_events=None,
                links=None,
                status=None,
                same_process_as_parent_span=None,
                span_kind=0,
            )
        ]

mock_exporter = mock.MagicMock()
        tracer = tracer_module.Tracer(exporter=mock_exporter,
                                      sampler=samplers.AlwaysOnSampler())

        return_value = "test"

        @tracer.trace_decorator()
        def test_decorator():
            return return_value

        returned = test_decorator()

        self.assertEqual(returned, return_value)
        self.assertEqual(mock_exporter.export.call_count, 1)
        exported_spandata = mock_exporter.export.call_args[0][0][0]
        self.assertIsInstance(exported_spandata, span_data.SpanData)
        self.assertEqual(exported_spandata.name, 'test_decorator')

def test_translate_time_events_invalid(self):

        ts = datetime.utcnow() + timedelta(seconds=-10)

        span_data = span_data_module.SpanData(
            context=span_context_module.SpanContext(
                trace_id='6e0c63257de34c92bf9efcd03927272e'),
            span_id='6e0c63257de34c92',
            time_events=[time_event_module.TimeEvent(timestamp=ts)],
            span_kind=span_module.SpanKind.SERVER,
            status=None,
            start_time=None,
            end_time=None,
            child_span_count=None,
            name=None,
            parent_span_id=None,
            attributes=None,
            same_process_as_parent_span=False,
            stack_trace=None,
            links=None)

def test_translate_status(self):
        span_data = span_data_module.SpanData(
            context=span_context_module.SpanContext(
                trace_id='6e0c63257de34c92bf9efcd03927272e'),
            span_id='6e0c63257de34c92',
            status=status_module.Status(
                code=2, message='ERR', details='details'),
            span_kind=span_module.SpanKind.SERVER,
            start_time=None,
            end_time=None,
            child_span_count=None,
            name=None,
            parent_span_id=None,
            attributes=None,
            same_process_as_parent_span=False,
            stack_trace=None,
            time_events=None,
            links=None)

name="name0",
                context=span_context_module.SpanContext(
                    trace_id='0e0c63257de34c92bf9efcd03927272e'),
                span_id='0e0c63257de34c92',
                parent_span_id=None,
                attributes=None,
                start_time=None,
                end_time=None,
                child_span_count=None,
                stack_trace=None,
                time_events=None,
                links=None,
                status=None,
                same_process_as_parent_span=None,
                span_kind=0),
            span_data_module.SpanData(
                name="name1",
                context=span_context_module.SpanContext(
                    trace_id='1e0c63257de34c92bf9efcd03927272e'),
                span_id='1e0c63257de34c92',
                parent_span_id=None,
                attributes=None,
                start_time=None,
                end_time=None,
                child_span_count=None,
                stack_trace=None,
                time_events=None,
                links=None,
                status=None,
                same_process_as_parent_span=None,
                span_kind=0)
        ]

def test_span_data_immutable(self):
        span_data = span_data_module.SpanData(
            name='root',
            context=None,
            span_id='6e0c63257de34c92',
            parent_span_id='6e0c63257de34c93',
            attributes={'key1': 'value1'},
            start_time=utils.to_iso_str(),
            end_time=utils.to_iso_str(),
            stack_trace=None,
            links=None,
            status=None,
            annotations=None,
            message_events=None,
            same_process_as_parent_span=None,
            child_span_count=None,
            span_kind=0,
        )

def test_translate_server_span_kindt(self):
        server_span_data = span_data_module.SpanData(
            context=span_context_module.SpanContext(
                trace_id='6e0c63257de34c92bf9efcd03927272e'),
            span_id='6e0c63257de34c92',
            span_kind=span_module.SpanKind.SERVER,
            child_span_count=1,
            start_time=None,
            end_time=None,
            name=None,
            parent_span_id=None,
            attributes=None,
            same_process_as_parent_span=False,
            stack_trace=None,
            time_events=None,
            links=None,
            status=None)

name='child_span',
                context=span_context.SpanContext(trace_id=trace_id),
                span_id='6e0c63257de34c92',
                parent_span_id='6e0c63257de34c93',
                attributes={'test_key': 'test_value'},
                start_time='2017-08-15T18:02:26.071158Z',
                end_time='2017-08-15T18:02:36.071158Z',
                child_span_count=None,
                stack_trace=None,
                time_events=None,
                links=None,
                status=None,
                same_process_as_parent_span=None,
                span_kind=0,
            ),
            span_data_module.SpanData(
                name='child_span',
                context=span_context.SpanContext(trace_id=trace_id),
                span_id='6e0c63257de34c92',
                parent_span_id='6e0c63257de34c93',
                attributes={'test_key': 1},
                start_time='2017-08-15T18:02:26.071158Z',
                end_time='2017-08-15T18:02:36.071158Z',
                child_span_count=None,
                stack_trace=None,
                time_events=None,
                links=None,
                status=None,
                same_process_as_parent_span=None,
                span_kind=None,
            ),
        ]

def format_legacy_trace_json(span_datas):
    """Formats a list of SpanData tuples into the legacy 'trace' dictionary
    format for backwards compatibility
    :type span_datas: list of :class:
            `~opencensus.trace.span_data.SpanData`
    :param list of opencensus.trace.span_data.SpanData span_datas:
        SpanData tuples to emit
    :rtype: dict
    :return: Legacy 'trace' dictionary representing given SpanData tuples
    """
    if not span_datas:
        return {}
    top_span = span_datas[0]
    assert isinstance(top_span, SpanData)
    trace_id = top_span.context.trace_id if top_span.context is not None \
        else None
    assert trace_id is not None
    return {
        'traceId': trace_id,
        'spans': [_format_legacy_span_json(sd) for sd in span_datas],
    }