 &#39;x-datadog-parent-id&#39;,
        &#39;x-datadog-sampling-priority&#39;,
        &#39;traceparent&#39;,
        &#39;tracestate&#39;,
        &#39;x-cloud-trace-context&#39;,
        &#39;grpc-trace-bin&#39;,
        &#39;user-agent&#39;,
        &#39;cookie&#39;,
        &#39;authorization&#39;,
        &#39;jwt&#39;,
    ]

    # ...

    for ihdr in incoming_headers:
        val = request.headers.get(ihdr)
        if val is not None:
            headers[ihdr] = val

    return headers</code></pre><