from urllib.parse import urlparse
o = urlparse("https://a...content-available-to-author-only...a.net:666/api/v1/")
print(o.hostname)
s = o.hostname.split('.', 1)[0]
print(s)
ZnJvbSB1cmxsaWIucGFyc2UgaW1wb3J0IHVybHBhcnNlCm8gPSB1cmxwYXJzZSgiaHR0cHM6Ly9hLi4uY29udGVudC1hdmFpbGFibGUtdG8tYXV0aG9yLW9ubHkuLi5hLm5ldDo2NjYvYXBpL3YxLyIpCnByaW50KG8uaG9zdG5hbWUpCnMgPSBvLmhvc3RuYW1lLnNwbGl0KCcuJywgMSlbMF0KcHJpbnQocyk=