Go的LookupAddr为什么在此期间结束？

I am doing a reverse ip lookup using Go:

hosts, err := net.LookupAddr("google.com")
if err != nil {
    fmt.Println(err)
}
fmt.Println(hosts)

Results:

[den02s02-in-f14.1e100.net.]

The same in Python:

addr1 = socket.gethostbyaddr('google.com')
print(addr1)

results:

('den02s02-in-f14.1e100.net', [], ['172.217.12.14'])

Why does the Go version end in period?

This is how a correct fully qualified domain name is supposed to be formatted. It tells anything reading that hostname that it is fully qualified and not partially qualified. Failure to output such FQDNs is common, and not necessarily a problem for most software. Until it is, of course.

Refs: Wikipedia, et al.