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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def zipkin_tween(handler, registry):
 """ Factory for pyramid tween to handle zipkin server logging. Note that even if the request isn't sampled, Zipkin attributes are generated and pushed into threadlocal storage, so `create_http_headers_for_new_span` and `zipkin_span` will have access to the proper Zipkin state. Consumes custom create_zipkin_attr function if one is set in the pyramid registry. :param handler: pyramid request handler :param registry: pyramid app registry :returns: pyramid tween """

    def tween(request):
        zipkin_settings = _get_settings_from_request(request)
        tracer = get_default_tracer()

        tween_kwargs = dict(
            service_name=zipkin_settings.service_name,
            span_name=zipkin_settings.span_name,
            zipkin_attrs=zipkin_settings.zipkin_attrs,
            transport_handler=zipkin_settings.transport_handler,
            host=zipkin_settings.host,
            port=zipkin_settings.port,
            add_logging_annotation=zipkin_settings.add_logging_annotation,
            report_root_timestamp=zipkin_settings.report_root_timestamp,
            context_stack=zipkin_settings.context_stack,
            max_span_batch_size=zipkin_settings.max_span_batch_size,
            encoding=zipkin_settings.encoding,
            kind=Kind.SERVER,
        )

        if zipkin_settings.firehose_handler is not None:
            tween_kwargs['firehose_handler'] = zipkin_settings.firehose_handler

        with tracer.zipkin_span(**tween_kwargs) as zipkin_context:
            response = handler(request)
            if zipkin_settings.use_pattern_as_span_name and request.matched_route:
                zipkin_context.override_span_name('{} {}'.format(
                    request.method,
                    request.matched_route.pattern,
                ))
            zipkin_context.update_binary_annotations(
                get_binary_annotations(request, response),
            )

            if zipkin_settings.post_handler_hook:
                zipkin_settings.post_handler_hook(request, response)

            return response

    return tween