I'm reading 'SRE with Java Microservices'(O'reilly)

"USL forecasting is a form of “derived” Meter in Micrometer and can be enabled as shown in Example 4-39. "

Example 4-39. Universal scalability law forecast configuration in Micrometer

UniversalScalabilityLawForecast
.builder(
registry
.find("http.server.requests")
.tag("uri", "/myendpoint")
.tag("status", s -> s.startsWith("2"))
)
.independentVariable(UniversalScalabilityLawForecast.Variable.THROUGHPUT)
// In this case, forecast to up to 1,000 requests/second (throughput)
.maximumForecast(1000)
.register(registry);

What and where is this class 'UniversalScalabilityLawForecast' in Micrometer library?? I can't find it github repository, google searching, no luck.

help me please.