Example handler:

def Handle_System_Timer(Timer):
#
# Timer = VT_BSTR
#
# Python defined timer events
#
  t=GetTimer(Timer)  #get the timer class
  if Timer=='T0':
    T0Timer()             #call user script T0Timer
    t.interval=1000     #set interval 1 sec
  elif Timer=='T1':
    T1Timer()             #call user script T1Timer
    t.active=0             #disable timer

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