From Denim Curlew, 3 Years ago, written in AutoCAD/IntelliCAD Lisp.
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  1. height = 100;
  2. twist_factor = 144;
  3. twist = height * twist_factor;
  4. radius = 3;
  5.  
  6. cylinder(height,r = radius,true,$fn = 360);
  7. linear_extrude(height = height, center = false, convexity = 10, twist = twist, $fn = 360){
  8.   translate([(radius/1.5), 0, 0]){
  9.     square([(radius/3),(radius/2)],false);
  10.   }
  11. }
  12.