import hou
selectedItems = hou.selectedItems()
num = len(selectedItems)
if num == 1:
select = selectedItems[0]
parent = select.parent()
for i in range(0,12):
null = parent.createNode("null")
null.setName("OUT_"+str(i),unique_name = True)
timeShift = parent.createNode("timeshift")
null.setInput(0,timeShift)
exp = "substr($OS,9,10)"
timeShift.setInput(0,select)
timeShift.parm("frame").deleteAllKeyframes()
timeShift.parm("frame").setExpression(exp)
else:
print "please select 1 node!"