Q:Generate a question about the following movie plot: Mother Gin Sling's is a casino in Shanghai where all the best and worst personalities come to drink and gamble and its proprietor Mother Gin Sling (Ona Munson) is a tough and astute business woman who laughs and jokes with even the leaders of the community. When she is told that she is being evicted by an English businessman, Sir Guy Charteris (Walter Huston) Gin Sling immediately digs up all the dirt she can find on the man. When one of her minions Dr. Omar (Victor Mature) takes up with a new visitor Poppy Charteris (Gene Tierney) to the gambling joint things are good- she loses more money each night even though she is advanced thousands from the bank to keep her coming back, but Dr. Omar convinces her to hock off all of her jewelry. Poppy is the daughter of Charteris and is addicted to more than gambling, so much so that Charteris sends her away before he accepts a dinner invitation from Gin Sling for Chinese New Year. At Gin Sling's party in the presence of many other high-level leaders of the city Gin Sling lets out some information that insures her fate on many levels.
A:
Who is the proprietor of Mother Gin Sling's?