Who are the seven immortal emperors who are so wild that they swallow the sky?

Willow is innocent. According to the report of Search Starting Point Fiction Network, in "Too Wild to Swallow Heaven", Liu Tianzhen finally became the seventh immortal emperor through a heavy postgraduate entrance examination with her golden finger. "Too Wild to Swallow Heaven" is a fantasy online novel serialized on Chinese website. The author is Ma Tie Qiao Fei.