code: def process_request(self, request):
          
          # Do not trace if the url is blacklisted
          if utils.disable_tracing_url(request.path, self.blacklist_paths):
              return
  
          # Add the request to thread local
          execution_context.set_opencensus_attr(
              REQUEST_THREAD_LOCAL_KEY,
              request)
  
          execution_context.set_opencensus_attr(
              'blacklist_hostnames',
              self.blacklist_hostnames)
  
          try:
              # Start tracing this request
              span_context = self.propagator.from_headers(
                  _DjangoMetaWrapper(_get_django_request().META))
  
              # Reload the tracer with the new span context
              tracer = tracer_module.Tracer(
                  span_context=span_context,
                  sampler=self.sampler,
                  exporter=self.exporter,
                  propagator=self.propagator)
  
              # Span name is being set at process_view
              span = tracer.start_span()
              span.span_kind = span_module.SpanKind.SERVER
              tracer.add_attribute_to_current_span(
                  attribute_key=HTTP_METHOD,
                  attribute_value=request.method)
              tracer.add_attribute_to_current_span(
                  attribute_key=HTTP_URL,
                  attribute_value=str(request.path))
  
              # Add the span to thread local
              # in some cases (exceptions, timeouts) currentspan in
              # response event will be one of a child spans.
              # let's keep reference to 'django' span and
              # use it in response event
              execution_context.set_opencensus_attr(
                  SPAN_THREAD_LOCAL_KEY,
                  span)
  
          except Exception:  # pragma: NO COVER
              log.error('Failed to trace request', exc_info=True)
docs: Called on each request, before Django decides which view to execute.
  
          :type request: :class:`~django.http.request.HttpRequest`
          :param request: Django http request.