new_contents: n = nuke.thisNode()
  
  if nuke.thisNode()['exportBool'].getValue():
  	point = n['onePtExport'].value()
  
  	X = 2
  	Y = 3
  	T = 6
  	R = 7
  	S = 8
      
  	_refFrame = int(n['refFrame'].getValue())
  
  	if not _refFrame:
  		_refFrame = nuke.frame()
  		n['refFrame'].setValue(_refFrame)
  		
  	nuke.frame(_refFrame)
  
  	choice = int(n['exportChoice'].getValue())
  	if 1 <= choice <= 2:
  		nuke.message('A relative link to trackers is not (yet) supported')
  		
  	else:
  		nuke.root().begin()
  		tra = nuke.createNode("Tracker4")
  		tra.setInput(0, None)
  	
  		tra['add_track'].execute()
  		
  		k = tra['tracks']
  		k.setAnimated()
  		for f in range(nuke.root().firstFrame(),nuke.root().lastFrame()+1):
  			k.setValueAt(n[point].valueAt(f)[0], f, X)
  			k.setValueAt(n[point].valueAt(f)[1], f, Y)
  			
  		if choice == 3:
  			tra['transform'].setValue('stabilize')
  			tra['reference_frame'].setValue(_refFrame)
  			
  		elif choice == 4:
  			tra['transform'].setValue('matchmove')
  			tra['reference_frame'].setValue(_refFrame)
  
subject: Create export_OneTracker.py