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Co-Authored-By: Kyle Nusbaum <kyle.nusbaum@datadoghq.com>

ddtrace/tracer/option.go

@@ -244,6 +244,7 @@ func WithSampler(s Sampler) StartOption {
 }
 
 // WithHTTPRoundTripper is deprecated. Please consider using WithHTTPClient instead.
+// The function allows customizing the underlying HTTP transport for emitting spans. 
 func WithHTTPRoundTripper(r http.RoundTripper) StartOption {
 	return WithHTTPClient(&http.Client{
 		Transport: r,