Here's a short story:

For most caffeine consumers, its chief benefit is that it helps you get more done. This is what makes it unusual, says Stephen Braun, author of Buzz: The Science and Lore of Alcohol and Caffeine. "Its appeal is that it helps us earn more money," he adds. "What makes it different from other drugs is that it's used as a productivity tool -- not for pleasure." Many of history's creative minds have also been associated with a large amount of caffeine consumption. According to one biographer, the French novelist and playwright Balzac drank as many as 50 cups of coffee a day. "Were it not for coffee one could not write, which is to say one could not live," he once insisted. For seven years, the film-maker David Lynch ate at the same Los Angeles diner every day, drinking up to seven sweetened cups of coffee "with lots of sugar" in one sitting, which he said would guarantee that "lots of ideas" arrived. Ludwig van Beethoven was said to have painstakingly counted out exactly 60 coffee beans per cup when he brewed coffee. Perhaps recent tales of caffeine excess featured the singer Robbie Williams, who reportedly consumed 36 cups of black coffee and 20 cans of Red Bull a day. It is the routine task itself, as much as the stimulating effects of caffeine, that makes the process so important, says Mason Currey, author of Daily Rituals: How Artists Work. "A lot of artists use the process of making coffee as a gateway to the creative process," he adds. "You need to get into the right mindset to do that sort of work, and the preparation process provides a focus." One problem with attempting to control caffeine, says Braun, is that it affects everyone differently -- it is impossible to work out a "safe" limit that works for everyone. "Eventually, you have to become your own scientist -- there isn't an alternative to careful self-experimentation," he says. (End of story)

Provide your best guess for the following question. Give ONLY the guess, no other words or explanation.

For example:

Guess: <most likely guess, as short as possible; not a complete sentence, just the guess!>

Here are a few examples of questions and answers:

Question: What is the main side effect of caffeine?
Guess: it helps you get more done

Question: What makes this more unique than other drugs?
Guess: it's used as a productivity tool

Question: What do many of the famous creative people have in common?
Guess: They have been associated with a large amount of caffeine consumption.

Question: What famous play writed would drink a ton of it?
Guess: Balzac

Question: How much did he drink?
Guess: 50 cups of coffee a day

Question: What would happen if he didn't?
Guess: he could not write

Question: What film maker was famous of eating at the same place?
Guess: David Lynch

Question: How much would he drink?
Guess: seven sweetened cups

Question: What famous composer was specific about his coffee?
Guess: Ludwig van Beethoven

Question: How?
Guess: he counted out exactly 60 coffee beans per cup

Question: What did a famous sing consume along side his coffee?
Guess: Red Bull

Now answer the following question in the same format.

Question: How much?

20 cans