Earlier this month at a D.C. screening at National Geographic’s headquarters, director Cherien Dabis said that watching films like Truffaut’s The 400 Blows were what finally allowed her to make her first feature. Realizing that one really could make a great story out of the experiences of one’s own life, Dabis decided to write what she knew. Of course, for every Truffaut there are a hundred writers and filmmakers for whom “write what you…