The wiki documentation seems to indicate that http://www.creationkit.com/EnableFastTravel_-_Game is a global function, so you shouldn't need to, but what I meant was adding a line like this near the top of your script:
import Game
I thought this might be necessary because I knew that http://www.creationkit.com/EnableFastTravel_-_Game is declared in the http://www.creationkit.com/Game_Script, and that the http://www.creationkit.com/Quest_Script doesn't extend Game, so I thought you might need to http://www.creationkit.com/Import the Game script in order to make EnableFastTravel available in your script.
Because the http://www.creationkit.com/Function_Reference#Function_Header keyword is used when declaring EnableFastTravel, this isn't necessary, as it should be accessible to any script.
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