// This is the OpenCensus FromContext function, implemented using opentelemetry's SpanFromContext
func (o *otelTracer) FromContext(ctx context.Context) *octrace.Span {
	otSpan := otel.SpanFromContext(ctx)
	return // convert the opentelemetry span into the OC span implementation
}

// This is the OpenCensus NewContext function, implemented using opentelemetry's ContextWithSpan
func (o *otelTracer) NewContext(parent context.Context, s *octrace.Span) context.Context {
        // Below, I need to call s.Internal() in order to have an interface I can cast to my internal type.
        // For example, my internal type could wrap an opentelemetry Span, which I could use in ContextWithSpan
	if myspan, ok := s.Internal().(*myspanimplementation); ok {
		return otel.ContextWithSpan(parent, // get an opentelemetry Span from myspan)
	}
	// The user must have created the octrace Span using a different tracer, and we don't know how to store it.
	return parent
}