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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def GetNewEventId(self, event_time=None):
 """Return a unique Event ID string."""

    if event_time is None:
      event_time = int(time.time() * 1e6)

    return "%s:%s:%s" % (event_time, socket.gethostname(), os.getpid())